[Federal Register Volume 81, Number 9 (Thursday, January 14, 2016)]
[Proposed Rules]
[Pages 2004-2052]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-33108]
[[Page 2003]]
Vol. 81
Thursday,
No. 9
January 14, 2016
Part II
Environmental Protection Agency
-----------------------------------------------------------------------
40 CFR Part 52
Approval, Disapproval and Promulgation of Air Quality Implementation
Plans; Partial Approval and Partial Disapproval of Air Quality
Implementation Plans and Federal Implementation Plan; Utah; Revisions
to Regional Haze State Implementation Plan; Federal Implementation Plan
for Regional Haze; Proposed Rule
Federal Register / Vol. 81 , No. 9 / Thursday, January 14, 2016 /
Proposed Rules
[[Page 2004]]
-----------------------------------------------------------------------
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R08-OAR-2015-0463; FRL--9939-43-Region 8]
Approval, Disapproval and Promulgation of Air Quality
Implementation Plans; Partial Approval and Partial Disapproval of Air
Quality Implementation Plans and Federal Implementation Plan; Utah;
Revisions to Regional Haze State Implementation Plan; Federal
Implementation Plan for Regional Haze
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
-----------------------------------------------------------------------
SUMMARY: The Environmental Protection Agency (EPA) is proposing to take
action pursuant to section 110 of the Clean Air Act (CAA or Act) on
State Implementation Plan (SIP) revisions submitted by the State of
Utah on June 4, 2015, and October 20, 2015 to implement the regional
haze program. The State's SIP revisions establish an alternative to
best available retrofit technology (BART) controls that would otherwise
be required to control nitrogen oxides (NOX) at PacifiCorp's
Hunter and Huntington power plants. The June 2015 SIP revision also
includes BART determinations for particulate matter with an aerodynamic
diameter of less than 10 micrometers (PM10) at these power
plants and provisions for making the NOX and PM10
BART emission limits federally enforceable. The CAA requires states to
prevent any future and remedy any existing man-made impairment of
visibility in national parks and wilderness areas designated as Class I
areas. Air emissions from the four electric generating units (EGUs) at
the two plants affected by this action cause or contribute to
visibility impairment at nine Class I areas including Grand Canyon,
Arches, Bryce Canyon and Zion National Parks. The EPA is issuing two
co-proposals in order to fully evaluate the State's submittals and the
public's input thereon. The EPA would work with the State on a revised
State plan should a partial disapproval and FIP be finalized.
DATES: Comments: Written comments must be received on or before March
14, 2016.
Public Hearing: A public hearing for this proposal is scheduled to
be held on Tuesday, January 26, 2016, at the Salt Lake City Public
Library, Main Library, from 1 p.m. until 5 p.m., and again from 6 p.m.
until 8 p.m. (local time).
ADDRESSES: The public hearing will be held at the Salt Lake City Public
Library, Main Library, 210 East 400 South, Salt Lake City, Utah 84111.
Submit your comments, identified by Docket ID No. EPA-R08-OAR-2015-
0463, to the Federal eRulemaking Portal: http://www.regulations.gov.
Follow the online instructions for submitting comments. Once submitted,
comments cannot be edited or removed from Regulations.gov. The EPA may
publish any comment received to its public docket. Do not submit
electronically any information you consider to be Confidential Business
Information (CBI) or other information whose disclosure is restricted
by statute. Multimedia submissions (audio, video, etc.) must be
accompanied by a written comment. The written comment is considered the
official comment and should include discussion of all points you wish
to make. The EPA will generally not consider comments or comment
contents located outside of the primary submission (i.e., on the web,
cloud, or other file sharing system). For additional submission
methods, the full EPA public comment policy, information about CBI or
multimedia submissions, and general guidance on making effective
comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.
Instructions: Direct your comments to Docket ID No. EPA-R08-OAR-
2015-0463. The EPA's policy is that all comments received will be
included in the public docket and may be made available online at
http://www.regulations.gov, including any personal information
provided, unless the comment includes information claimed to be
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through www.regulations.gov
or email. The www.regulations.gov Web site is an ``anonymous access''
system, which means EPA will not know your identity or contact
information unless you provide it in the body of your comment. If you
send an email comment directly to EPA, without going through
www.regulations.gov your email address will be automatically captured
and included as part of the comment that is placed in the public docket
and made available on the Internet. If you submit an electronic
comment, EPA recommends that you include your name and other contact
information in the body of your comment and with any disk or CD-ROM you
submit. If EPA cannot read your comment due to technical difficulties
and cannot contact you for clarification, EPA may not be able to
consider your comment. Electronic files should avoid the use of special
characters, any form of encryption, and be free of any defects or
viruses. For additional information about EPA's public docket visit the
EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
For additional instructions on submitting comments, go to section I,
General Information, of the SUPPLEMENTARY INFORMATION section of this
document.
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. 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 a.m. to 4 p.m., excluding
federal holidays.
FOR FURTHER INFORMATION CONTACT: Gail Fallon, Air Program, EPA, Region
8, Mailcode 8P-AR, 1595 Wynkoop Street, Denver, Colorado, 80202-1129,
(303) 312-6281, [email protected].
SUPPLEMENTARY INFORMATION:
Public Hearing
The public hearing will provide interested parties the opportunity
to present data, views, or arguments concerning the proposed action.
The EPA may ask clarifying questions during the oral presentations, but
will not respond to the presentations at that time. Written statements
and supporting information submitted during the comment period will be
considered with the same weight as oral comments and supporting
information presented at the public hearing. The hearing officer may
limit the time available for each commenter to address the proposal to
5 minutes or less if the hearing officer determines it to be
appropriate. The limitation is to ensure that everyone who wants to
make a comment has the opportunity to do so. We will not be providing
equipment for commenters to show overhead slides or make computerized
slide presentations. Any person may provide written or oral
[[Page 2005]]
comments and data pertaining to our proposal at the public hearings.
Verbatim transcripts, in English, of the hearings and written
statements will be included in the rulemaking docket.
Table of Contents
I. General Information
II. Overview of Proposed Actions
A. Brief Description of These Co-Proposals
1. Summary of Proposal To Approve the SIP
2. Summary of Proposal To Partially Approve and Partially
Disapprove the SIP and Propose a FIP
III. Background and Requirements for Regional Haze SIPs and Utah
Submittals
A. Statutory and Regulatory Background
1. Regional Haze
2. Requirements of the CAA and EPA's Regional Haze Rule (RHR)
3. Roles of Agencies in Addressing Regional Haze
4. Development of the Requirements for 40 CFR 51.309
5. SIP and FIP Background
B. Requirements for Regional Haze SIPs Applicable to This
Proposal
1. The CAA and the Regional Haze Rule
2. Determination of Baseline, Natural and Current Visibility
Conditions
3. Best Available Retrofit Technology
4. Monitoring, Recordkeeping and Reporting
5. Consultation With States and Federal Land Managers (FLMs)
C. Requirements for Regional Haze SIPs Submitted Under 40 CFR
51.309
1. Projection of Visibility Improvement
2. Stationary Source Reductions
a. Sulfur Dioxide Emission Reductions
b. Provisions for Stationary Source Emissions of Nitrogen Oxides
and Particulate Matter
D. General Requirements for PM10 and NOX
Alternative Programs Under the Regional Haze Rule and the ``Better-
Than-BART Demonstration''
E. Summary of State Regional Haze Submittals and EPA Actions
1. 2008 and 2011 Utah RH SIPs
2. 2012 EPA Action on 2011 and 2008 Utah RH SIPs
3. 2013 Litigation
4. 2015 Utah RH SIPs
IV. Utah's Regional Haze SIP
A. Summary of Elements Under EPA's Previous Actions Upon Which
We Are Relying
1. Affected Class I Areas
2. BART-Eligible Sources
3. Sources Subject-to-BART
B. Summary of Utah's BART Alternative and PM10 BART
SIP Revision
1. Utah BART Alternative
2. PM10 BART Determinations
3. Monitoring, Recordkeeping and Reporting
C. Summary of Utah's Demonstration for Alternative Program
1. A List of All BART-Eligible Sources Within the State
2. A List of All BART-Eligible Sources and All BART Source
Categories Covered by the Alternative Program
3. Analysis of BART and Associated Emission Reductions
Achievable
4. Analysis of Projected Emissions Reductions Achievable Through
the BART Alternative
5. A Determination That the Alternative Achieves Greater
Reasonable Progress Than Would Be Achieved Through the Installation
and Operation of BART
a. Annual Emissions Comparison for Visibility-Impairing
Pollutants
b. Improvement in the Number of Days With Significant Visibility
Impairment
c. 98th Percentile Impact (dv)
d. Annual Average Impact (dv)
e. 90th Percentile Impact (dv)
f. Timing for the Emissions Reductions
g. IMPROVE Monitoring Data
h. Energy and Non-Air Quality Benefits
i. Cost
6. Requirement That Emission Reductions Take Place During Period
of First Long-Term Strategy
7. Demonstration That Emission Reductions From Alternative
Program Will Be Surplus
D. Summary of Utah's Enforceable Commitment SIP Revision
E. Consultation With FLMs
V. EPA's Evaluation and Proposed Approval of Utah's Regional Haze
SIP
A. Basis for Proposed Approval
B. Utah BART Alternative
1. Summary of Utah BART Alternative
2. Demonstration of Greater Reasonable Progress for the
Alternative Program
a. A List of All BART-Eligible Sources Within the State
b. A List of All BART-Eligible Sources and All BART Source
Categories Covered by the Alternative Program
c. Analysis of BART and Associated Emission Reductions
d. Analysis of Projected Emissions Reductions Achievable Through
the BART Alternative
e. A Determination That the Alternative Achieves Greater
Reasonable Progress Than Would Be Achieved Through the Installation
and Operation of BART
f. Evaluation of the Weight of Evidence
g. Requirement That Emission Reductions Take Place During Period
of First Long-Term Strategy
h. Demonstration That Emission Reductions From Alternative
Program Will Be Surplus
C. PM10 BART Determinations
D. Monitoring, Recordkeeping, and Reporting
E. Consultation With FLMs
VI. EPA's Evaluation and Proposed Partial Approval and Partial
Disapproval of Utah's Regional Haze SIP
A. Basis for Proposed Partial Disapproval and Partial Approval
B. Utah BART Alternative
1. Summary of Utah BART Alternative
2. Demonstration of Greater Reasonable Progress for Alternative
Program
a. A List of All BART-Eligible Sources Within the State
b. A List of All BART-Eligible Sources and All BART Source
Categories Covered by the Alternative Program
c. Analysis of BART and Associated Emission Reductions
Achievable
d. Analysis of Projected Emissions Reductions Achievable Through
the BART Alternative
e. A Determination That the Alternative Achieves Greater
Reasonable Progress Than Would Be Achieved Through the Installation
and Operation of BART
f. Evaluation of the Weight of Evidence
g. Evaluation That Emission Reductions Take Place During Period
of First Long-Term Strategy
h. Demonstration That Emission Reductions From Alternative
Program Will Be Surplus
C. Monitoring, Recordkeeping and Reporting for Utah's BART
Alternative
D. Proposed Federal Implementation Plan
1. BART Evaluations
a. Costs of Compliance
b. Visibility Impact Modeling
2. Hunter Power Plant
a. Hunter Unit 1
b. Hunter Unit 2
3. Huntington Power Plant
a. Huntington Unit 1
b. Huntington Unit 2
4. Federal Monitoring, Recordkeeping, and Reporting
E. PM10 BART Determinations
F. Consultation With FLMs
VII. EPA's Proposed Actions
A. Proposed Approval
B. Proposed Partial Disapproval/Approval and Federal
Implementation Plan
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act (UMRA)
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
I. National Technology Transfer and Advancement Act
J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations
I. General Information
What should I consider as I prepare my comments for EPA?
1. Submitting Confidential Business Information (CBI). Do not
submit CBI to EPA through http://www.regulations.gov or email. Clearly
mark the part or all of the information that you claim to be CBI. For
CBI information on a disk or CD-ROM that you mail to EPA, mark the
outside of the disk or CD-ROM as CBI and then identify electronically
within the disk or CD ROM the specific
[[Page 2006]]
information that is claimed as CBI. In addition to one complete version
of the comment that includes information claimed as CBI, a copy of the
comment that does not contain the information claimed as CBI must be
submitted for inclusion in the public docket. Information so marked
will not be disclosed except in accordance with procedures set forth in
40 CFR part 2.
2. Tips for preparing your comments. When submitting comments,
remember to:
Identify the rulemaking by docket number and other
identifying information (subject heading, Federal Register, date, and
page number);
Follow directions and organize your comments;
Explain why you agree or disagree;
Suggest alternatives and substitute language for your
requested changes;
Describe any assumptions and provide any technical
information and/or data that you used;
If you estimate potential costs or burdens, explain how
you arrived at your estimate in sufficient detail to allow for it to be
reproduced;
Provide specific examples to illustrate your concerns, and
suggest alternatives;
Explain your views as clearly as possible, avoiding the
use of profanity or personal threats; and
Make sure to submit your comments by the comment period
deadline identified.
II. Overview of Proposed Actions
The State of Utah submitted SIP revisions on June 4, 2015, and
October 20, 2015, to fulfill the CAA requirement to meet the
requirements for the Best Available Retrofit Technology (BART) in the
Regional Haze Rule (RHR) for the pollutants NOX and
PM10. As described more fully in Section III, the purpose of
the RHR is to remedy and prevent impairment of visibility in Class I
areas resulting from anthropogenic air pollution. Instead of
establishing BART controls for NOX, Utah's SIP revisions
contain an alternative to BART. The revisions also include BART
controls for PM10. The idea of a BART alternative, which can
take into account (and even encourage) plans that take into account
state specific situations is a reasonable one, and one EPA supports
where consistent with the CAA and RHR.
The State's SIP contains a NOX BART Alternative and
metrics to evaluate the BART Alternative. In light of the variety of
metrics Utah used, this is a complicated analysis and EPA considered
the State's BART Alternative in the context of other previous decisions
we and the states have made. EPA carefully analyzed the SIP revisions
and the supporting information submitted by the State. We also
conducted additional analyses, which are included with this proposal.
Based on a careful consideration of all of this information, EPA is
proposing and soliciting comments on two different actions: A proposal
to approve the State SIP in its entirety,\1\ and a proposal to
partially approve and partially disapprove the State SIP and propose a
FIP.\2\ EPA takes seriously its decision to co-propose these two
actions (disapprove part of the State's plan, alongside proposing to
approve it), as it is preferable that the regional haze program be
implemented through state plans. As part of its oversight
responsibilities, EPA must be able to find that the state plan is
consistent with the requirements of the Act. In this instance, we
developed analyses and rationale supporting both a proposed approval
and a proposed partial approval and partial disapproval, and we solicit
input on each proposal. EPA intends to finalize only one proposal,
although the details of our final action may differ somewhat from what
is presented here based on any comments and additional information we
receive.
---------------------------------------------------------------------------
\1\ Our proposed approval for one element, reporting for PM BART
limits, is a conditional approval based on a commitment from Utah to
provide a SIP revision to address this element. See section V.D of
this document for a more detailed explanation.
\2\ In March 2015, conservation groups sued EPA in the U.S.
District Court for the District of Colorado alleging that EPA failed
to promulgate a regional haze FIP for Utah within the two-year
period allowed by CAA section 110(c). See Wildearth Guardians v.
McCarthy, Case No. 1:15-cv-oo630-MSK-KLM, at *1-2 (D. Colo. Mar. 27,
2015). EPA entered into a consent decree resolving this dispute
requiring EPA to sign notices of proposed and final rulemaking for
the regional haze requirements for Utah by December 16, 2015 and
June 1, 2016, respectively. The signing of this proposed rule
partially fulfills EPA's obligations under the consent decree. See
id. (Doc. 60, Motion to Enter Consent Decree filed on December 8,
2015).
---------------------------------------------------------------------------
Deciding whether to approve the State SIP entails an evaluation of
Utah's SIP revision with respect to three elements in the RHR: (1)
``[a] demonstration that the emissions trading program or other
alternative measure will achieve greater reasonable progress than would
have resulted from the installation and operation of BART at all
sources subject to BART in the State and covered by the alternative
program''; \3\ (2) ``[a] requirement that all necessary emission
reductions take place during the period of the first long-term strategy
for regional haze''; \4\ and (3) ``[a] demonstration that the emissions
reductions resulting from the alternative measure will be surplus to
those reductions resulting from measures adopted to meet requirements
of the CAA as of the baseline date of the SIP.'' \5\
---------------------------------------------------------------------------
\3\ 40 CFR 51.308(e)(2)(i).
\4\ 40 CFR 51.308(e)(2)(iii).
\5\ 40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------
For the first element, the determination that the alternative
measure will achieve greater reasonable progress than BART, the State
must provide the following: (1) A list of all BART-eligible sources
within the State; (2) a list of all BART-eligible sources and all BART
source categories covered by the alternative program; (3) an analysis
of BART and associated emission reductions; (4) an analysis of the
projected emission reductions achievable through the BART alternative;
and (5) a determination that the alternative achieves greater
reasonable progress than would be achievable through the installation
and operation of BART. A State has several options for making the
greater reasonable progress determination; \6\ in this instance, the
State elected to use two separate approaches.
---------------------------------------------------------------------------
\6\ 40 CFR 51.308(e)(2)(i)(E); 40 CFR 51.308(e)(3).
---------------------------------------------------------------------------
EPA's evaluation of the BART Alternative therefore entails
consideration of both of the State's analyses. As described in our 2006
revisions to the RHR, concerning BART alternatives, ``[t]he State's
discretion in this area is subject to the condition that it must be
reasonably exercised and that its decisions be supported by adequate
documentation of its analyses.'' \7\ As presented in section V, several
of the metrics in the State's analyses appear to support a
determination that a BART Alternative presented by the State achieves
greater reasonable progress than BART. However, several other metrics
in the State's analyses do not appear to support a conclusion that the
BART Alternative achieves greater reasonable progress. The complexity
of our evaluation leads us to propose and solicit comment on two
conclusions and courses of action: (1) The State's submittal meets the
test above and we approve the BART Alternative; or (2) the State's
submittal falls short of meeting this test and we disapprove the BART
Alternative and promulgate a FIP for NOX BART. We request
comment on all aspects of each proposal.
---------------------------------------------------------------------------
\7\ 71 FR 60612, 60621 (Oct. 13, 2006).
---------------------------------------------------------------------------
Given the complexities in evaluating these co-proposals, EPA wants
to ensure that our final decision is based on the best and most
currently available data and information, and is taken with the fullest
possible consideration of public input. Therefore, in addition to
seeking comments on the co-proposals, we are
[[Page 2007]]
also asking if interested parties have additional information or
analysis on the co-proposals, for example, analysis related to the
modeled visibility benefits of the BART Alternative compared to BART.
In light of any such information, we are asking whether interested
parties think the Agency should consider BART Alternatives or BART
control technology options that are related to what we propose and that
could be finalized as our FIP (if we disapprove the Utah SIP submittal
in our final action). The Agency is also asking if interested parties
have additional information or comments on the proposed timing of
compliance.
The Agency will take the comments and testimony received, as well
as any further SIP revisions received from the State prior to our final
action, into consideration in our final promulgation. As noted above,
additional information and comments may lead the Agency to adopt final
SIP and/or FIP regulations that differ somewhat from the co-proposals
presented here regarding the BART Alternative, BART control technology
option or emission limits, or impact other proposed regulatory
provisions. EPA's final action will fully consider these complex issues
and the comments received, which will result in the selection of a
final action that meets the CAA and regulatory requirements requiring
development and implementation of plans to ensure reasonable progress
toward improving visibility in mandatory Class I areas by reducing
emissions that cause or contribute to regional haze.
A. Brief Description of These Co-Proposals
1. Summary of Proposal To Approve the SIP
As explained more fully later, we are proposing to approve these
aspects of the State's June 4, 2015 SIP submittal:
NOX BART Alternative, including NOX
emission reductions from Hunter Units 1, 2, and 3, Huntington Units 1
and 2, and Carbon Units 1 and 2, and sulfur dioxide (SO2)
and PM10 emission reductions from Carbon Units 1 and 2.
BART determinations and emission limits for
PM10 at Hunter Units 1 and 2 and Huntington Units 1 and 2.
Monitoring, recordkeeping, and reporting requirements for
units subject to the BART Alternative and the PM10 emission
limits.
We are proposing to approve these elements of the State's October
20, 2015 SIP submittal:
Enforceable commitments to revise SIP section XX.D.3.c and
state rule R307-150 by March 2018 to clarify emission inventory
requirements for tracking compliance with the SO2 milestone
and properly accounting for the SO2 emission reductions due
to the closure of the Carbon plant.
2. Summary of Proposal to Partially Approve and Partially Disapprove
the SIP and Propose a FIP
We are proposing to approve these elements of the State's SIP
submittals:
BART determinations and emission limits for
PM10 at Hunter Units 1 and 2, and Huntington Units 1 and 2.
Monitoring, recordkeeping, and reporting requirements for
units subject to the PM10 emission limits.
We are proposing to disapprove these aspects of the State's June 4,
2015 SIP:
NOX BART Alternative, including NOX
emission reductions from Hunter Units 1, 2, and 3, Huntington Units 1
and 2, and Carbon Units 1 and 2, and SO2 and PM10
emission reductions from Carbon Units 1 and 2.
We are proposing to disapprove the State's October 20, 2015 SIP
submittal.
We are proposing promulgation of a FIP to address the deficiencies
in the Utah regional haze SIPs that are identified in this notice. The
proposed FIP includes the following elements:
NOX BART determinations and emission limits for
Hunter Units 1 and 2 and Huntington Units 1 and 2.
Monitoring, recordkeeping, and reporting requirements for
NOX at Hunter Units 1 and 2, and Huntington Units 1 and 2.
If we partially disapprove the SIP, and promulgate a FIP, the State
may submit a SIP revision to supersede the FIP. If we determine that
the SIP revision is approvable, regardless of whether or not its terms
match those of our final FIP, we would propose to approve such a SIP
revision. If we issue a final FIP, we encourage the State to submit a
SIP revision to replace the FIP.
III. Background and Requirements for Regional Haze SIPs and Utah
Submittals
A. Statutory and Regulatory Background
1. Regional Haze
Regional haze is visibility impairment that is produced by numerous
sources that are located across a broad geographic area and emit fine
particles (PM2.5) (e.g., sulfates, nitrates, organic carbon
(OC), elemental carbon (EC), and soil dust), and their precursors
(e.g., SO2, NOX, and in some cases, ammonia
(NH3) and volatile organic compounds (VOC)). Coarse PM also
impairs visibility. Fine particle precursors react in the atmosphere to
form PM2.5, which impairs visibility by scattering and
absorbing light. Visibility impairment reduces the clarity, color, and
visible distance that one can see, PM2.5 can also cause
serious health effects and mortality in humans and contributes to
environmental effects such as acid deposition and eutrophication.
Coarse PM also can cause adverse health effects.
Data from the existing visibility monitoring network, the
``Interagency Monitoring of Protected Visual Environments'' (IMPROVE)
monitoring network, show that at the time the regional haze rule was
finalized in 1999, visibility impairment caused by air pollution
occurred virtually all the time at most national parks and wilderness
areas. The average visual range \8\ in many Class I areas (i.e.,
national parks, wilderness areas, and international parks meeting
certain size criteria) in the western U.S. was 62-93 miles, but in some
Class I areas, these visual ranges may have been impacted by natural
wildfire and dust episodes.\9\ In most of the eastern Class I areas of
the U.S., the average visual range was less than 19 miles, ``or about
one-fifth of the visual range that would exist under estimated natural
conditions.'' \10\
---------------------------------------------------------------------------
\8\ Visual range is the greatest distance, in kilometers or
miles, at which a dark object can be viewed against the sky.
\9\ 64 FR 35715, 35716 (July 1, 1999).
\10\ Id.
---------------------------------------------------------------------------
2. Requirements of the CAA and EPA's Regional Haze Rule (RHR)
In section 169A of the 1977 Amendments to the CAA, Congress created
a program for protecting visibility in the nation's national parks and
wilderness areas. This section of the CAA establishes ``as a national
goal the prevention of any future, and the remedying of any existing,
impairment of visibility in mandatory class I Federal areas which
impairment results from manmade air pollution.'' \11\ On
[[Page 2008]]
December 2, 1980, EPA promulgated regulations to address visibility
impairment in Class I areas that are ``reasonably attributable'' to a
single source or small group of sources, i.e., reasonably attributable
visibility impairment.\12\ These regulations represented the first
phase in addressing visibility impairment. EPA deferred action on
regional haze that emanates from a variety of sources until monitoring,
modeling and scientific knowledge about the relationships between
pollutants and visibility impairment were improved.
---------------------------------------------------------------------------
\11\ 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 (Nov. 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.''
\12\ 45 FR 80084, 80084 (Dec. 2, 1980).
---------------------------------------------------------------------------
Congress added section 169B to the CAA in 1990 to address regional
haze issues. EPA promulgated a rule to address regional haze on July 1,
1999.\13\ The RHR revised the existing visibility regulations to
integrate into the regulation provisions addressing regional haze
impairment 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 EPA's visibility protection
regulations at 40 CFR 51.300 through 309. Some of the main elements of
the regional haze requirements are summarized later in section III.C of
this preamble. The requirement to submit a regional haze SIP applies to
all 50 states, the District of Columbia, and the Virgin Islands. 40 CFR
51.308(b) requires states to submit the first implementation plan
addressing regional haze visibility impairment no later than December
17, 2007.\14\
---------------------------------------------------------------------------
\13\ 64 FR 35714, 35714 (July 1, 1999) (codified at 40 CFR part
51, subpart P).
\14\ EPA's RHR requires subsequent updates to the regional haze
SIPs. 40 CFR 51.308(g) through (i).
---------------------------------------------------------------------------
Once EPA has found that a state has failed to make a required
submission, EPA is required to promulgate a FIP within two years unless
the state submits a SIP and the Agency approves it within the two-year
period.\15\
---------------------------------------------------------------------------
\15\ 42 U.S.C. 7410(c)(1).
---------------------------------------------------------------------------
3. Roles of Agencies in Addressing Regional Haze
Successful implementation of the regional haze program requires
long-term regional coordination among states, tribal governments, and
various federal agencies. As noted previously, pollution affecting the
air quality in Class I areas can be transported over long distances,
even hundreds of kilometers. Therefore, to effectively address the
problem of visibility impairment in Class I areas, states need to
develop strategies in coordination with one another, taking into
account the effect of emissions from one jurisdiction on the air
quality in another.
Because the pollutants that lead to regional haze can originate
from sources located across broad geographic areas, EPA has encouraged
the states and tribes across the United States to address visibility
impairment from a regional perspective. Five regional planning
organizations (RPOs) were created to address regional haze and related
issues. The RPOs first evaluated technical information to better
understand how their states and tribes impact Class I areas across the
country, and then pursued the development of regional strategies to
reduce emissions of pollutants that lead to regional haze.
The Western Regional Air Partnership (WRAP) RPO is a collaborative
effort of state governments, tribal governments, and various federal
agencies established to initiate and coordinate activities associated
with the management of regional haze, visibility and other air quality
issues in the western United States. WRAP member state governments
include: Alaska, Arizona, California, Colorado, Idaho, Montana, New
Mexico, North Dakota, Oregon, South Dakota, Utah, Washington, and
Wyoming. Tribal members include Campo Band of Kumeyaay Indians,
Confederated Salish and Kootenai Tribes, Cortina Indian Rancheria, Hopi
Tribe, Hualapai Nation of the Grand Canyon, Native Village of Shungnak,
Nez Perce Tribe, Northern Cheyenne Tribe, Pueblo of Acoma, Pueblo of
San Felipe, and Shoshone-Bannock Tribes of Fort Hall.
4. Development of the Requirements for 40 CFR 51.309
EPA's RHR provides two paths to address regional haze. One is 40
CFR 51.308, requiring states to perform individual point source BART
determinations and evaluate the need for other control strategies.
These strategies must be shown to make ``reasonable progress'' in
improving visibility in Class I areas inside the state and in
neighboring jurisdictions. The other method for addressing regional
haze is through 40 CFR 51.309, and is an option for nine states termed
the ``Transport Region States,'' which include: Arizona, California,
Colorado, Idaho, Nevada, New Mexico, Oregon, Utah, and Wyoming. By
meeting the requirements under 40 CFR 51.309, states can be deemed to
be making reasonable progress toward the national goal of achieving
natural visibility conditions for the 16 Class I areas on the Colorado
Plateau.
Section 309 requires participating states to adopt regional haze
strategies that are based on recommendations from the Grand Canyon
Visibility Transport Commission (GCVTC) for protecting the 16 Class I
areas on the Colorado Plateau.\16\ The EPA established the GCVTC on
November 13, 1991. The purpose of the GCVTC was to assess information
about the adverse impacts on visibility in and around the 16 Class I
areas on the Colorado Plateau and to provide policy recommendations to
EPA to address such impacts. Section 169B of the CAA called for the
GCVTC to evaluate visibility research, as well as other available
information, pertaining to adverse impacts on visibility from potential
or projected growth in emissions from sources located in the region.
The GCVTC determined that all Transport Region States could potentially
impact the Class I areas on the Colorado Plateau. The GCVTC submitted a
report to EPA in 1996 with its policy recommendations for protecting
visibility for the Class I areas on the Colorado Plateau. Provisions of
the 1996 GCVTC report include: Strategies for addressing smoke
emissions from wildland fires and agricultural burning; provisions to
prevent pollution by encouraging renewable energy development; and
provisions to manage clean air corridors (CACs), mobile sources, and
wind-blown dust, among other things. The EPA codified these
recommendations as an option available to states as part of the 1999
RHR.\17\
---------------------------------------------------------------------------
\16\ The Colorado Plateau is a high, semi-arid tableland in
southeast Utah, northern Arizona, northwest New Mexico, and western
Colorado. The 16 mandatory Class I areas are as follows: Grand
Canyon National Park, Mount Baldy Wilderness, Petrified Forest
National Park, Sycamore Canyon Wilderness, Black Canyon of the
Gunnison National Park Wilderness, Flat Tops Wilderness, Maroon
Bells Wilderness, Mesa Verde National Park, Weminuche Wilderness,
West Elk Wilderness, San Pedro Parks Wilderness, Arches National
Park, Bryce Canyon National Park, Canyonlands National Park, Capital
Reef National Park, and Zion National Park.
\17\ 64 FR 35714, 35749 (July 1, 1999).
---------------------------------------------------------------------------
EPA determined that the GCVTC strategies would provide for
reasonable progress in mitigating regional haze if supplemented by an
annex containing quantitative emission reduction milestones and
provisions for a trading program or other alternative measure.\18\
Thus, the 1999 RHR required that western states submit an annex to the
GCVTC report with quantitative milestones and detailed guidelines for
an alternative program in order to establish the GCVTC recommendations
as an alternative approach to fulfilling the section 308 requirements
for compliance with the RHR. In September
[[Page 2009]]
2000, the WRAP, which is the successor organization to the GCVTC,
submitted an annex to EPA. The annex contained SO2 emissions
reduction milestones and detailed provisions of a backstop trading
program to be implemented automatically if voluntary measures failed to
achieve the SO2 milestones. EPA codified the annex on June
5, 2003 at 40 CFR 51.309(h).\19\
---------------------------------------------------------------------------
\18\ 64 FR 35714, 35749, 35756.
\19\ 68 FR 33764, 33767 (June 5, 2003).
---------------------------------------------------------------------------
Five western states, including Utah, submitted implementation plans
under section 309 in 2003. EPA was challenged by the Center for Energy
and Economic Development (CEED) on the validity of the annex
provisions. In CEED v. EPA, the DC Circuit Court of Appeals vacated EPA
approval of the WRAP annex.\20\ In response to the court's decision,
EPA vacated the annex requirements adopted under 40 CFR 51.309(h), but
left in place the stationary source requirements in 40 CFR
51.309(d)(4).\21\ The requirements under 40 CFR 51.309(d)(4) contain
general requirements pertaining to stationary sources and market
trading, and allow states to adopt alternatives to the point source
application of BART.
---------------------------------------------------------------------------
\20\ Ctr. for Energy & Econ. Dev. v. EPA, 398 F.3d 653, 654
(D.C. Cir. 2005).
\21\ 71 FR 60612, 60612 (Oct. 13, 2006).
---------------------------------------------------------------------------
5. SIP and FIP Background
The CAA requires each state to develop plans to meet various air
quality requirements, including protection of visibility.\22\ The plans
developed by a state are referred to as SIPs. A state must submit its
SIPs and SIP revisions to EPA for approval. Once approved, a SIP is
enforceable by EPA and citizens under the CAA, which is also known as
being federally enforceable. If a state fails to make a required SIP
submittal or if we find that a state's required submittal is incomplete
or not approvable, then we must promulgate a FIP to fill this
regulatory gap.\23\ As discussed elsewhere in this preamble, one of the
proposals would disapprove aspects of Utah's regional haze SIP and
promulgate a FIP to address the deficiencies in Utah's regional haze
SIP, should we disapprove the SIP in our final action.
---------------------------------------------------------------------------
\22\ 42 U.S.C. 7410(a), 7491, and 7492(a), 169A, and 169B.
\23\ 42 U.S.C. 7410(c)(1).
---------------------------------------------------------------------------
B. Requirements for Regional Haze SIPs Applicable to This Proposal
1. The CAA and the Regional Haze Rule
Regional haze SIPs must assure reasonable progress towards the
national goal of achieving natural visibility conditions in Class I
areas. Section 169A of the CAA and EPA's implementing regulations
require states to establish long-term strategies for making reasonable
progress toward meeting this goal. Implementation plans must also give
specific attention to certain stationary sources that were in existence
on August 7, 1977, but were not in operation before August 7, 1962, and
require these sources, where appropriate, to install BART controls for
the purpose of eliminating or reducing visibility impairment. The
specific regional haze SIP requirements are discussed in further detail
later on.
2. Determination of Baseline, Natural, and Current Visibility
Conditions
The RHR establishes the deciview (dv) as the principal metric or
unit for expressing visibility.\24\ This visibility metric expresses
uniform changes in the degree of haze in terms of common increments
across the entire range of visibility conditions, from pristine to
extremely hazy conditions. Visibility expressed in deciviews is
determined by using air quality measurements to estimate light
extinction and then transforming the value of light extinction using a
logarithmic function. The dv is a more useful measure for tracking
progress in improving visibility than light extinction itself because
each dv change is an equal incremental change in visibility perceived
by the human eye. Most people can detect a change in visibility at one
dv.\25\
---------------------------------------------------------------------------
\24\ See 70 FR 39104, 39118 (July 6, 2005).
\25\ The preamble to the RHR provides additional details about
the deciview (dv) scale. 64 FR 35714, 35725 (July 1, 1999).
---------------------------------------------------------------------------
The dv is used in expressing reasonable progress goals (RPGs, which
are interim visibility goals towards meeting the national visibility
goal), in defining baseline, current, and natural conditions; and in
tracking changes in visibility. The regional haze SIPs must contain
measures that ensure ``reasonable progress'' toward the national goal
of preventing and remedying visibility impairment in Class I areas
caused by anthropogenic emissions that cause or contribute to regional
haze. The national goal is a return to natural conditions, i.e. to
reach a state at which anthropogenic sources of air pollution no longer
impair visibility in Class I areas.
To track changes in visibility over time at each of the 156 Class I
areas covered by the visibility program,\26\ and as part of the process
for determining reasonable progress, states must calculate the degree
of existing visibility impairment at each Class I area at the time of
each regional haze SIP submittal and review progress every five years,
midway through each 10-year implementation period. To do this, the RHR
requires states to determine the degree of impairment (in deciviews)
for the average 20 percent least impaired (``best'') and 20 percent
most impaired (``worst'') visibility days over a specified time period
at each of their Class I areas. In addition, states must also develop
an estimate of natural visibility conditions for the purpose of
comparing progress toward the national goal. Natural visibility is
determined by estimating the natural concentrations of pollutants that
cause visibility impairment and then calculating total light extinction
based on those estimates. In 2003, EPA provided guidance to states
regarding how to calculate baseline, natural and current visibility
conditions.\27\ Subsequently, the Natural Haze Levels II Committee
developed updated estimates of natural haze for average natural
conditions and for the averages of the best 20% and worst 20% natural
condition days \28\ that have been used by states and EPA in visibility
assessments.
---------------------------------------------------------------------------
\26\ 40 CFR 81.401-437.
\27\ Guidance for Estimating Natural Visibility Conditions Under
the Regional Haze Rule, EPA-454/B-03-005, available at http://www3.epa.gov/ttn/caaa/t1/memoranda/rh_envcurhr_gd.pdf, (hereinafter
referred to as ``our 2003 Natural Visibility Guidance'') (Sept.
2003) (documents identified with Internet addresses are available in
the docket) ; Guidance for Tracking Progress Under the Regional Haze
Rule, EPA-454/B-03-004, available at http://www3.epa.gov/ttnamti1/files/ambient/visible/tracking.pdf (hereinafter referred to as our
``2003 Tracking Progress Guidance'') (Sept. 2003).
\28\ ``Natural Haze Levels II: Application of the New IMPROVE
Algorithm to Natural Species Concentrations Estimates'', Final
Report by the Natural Haze Levels II Committee to the RPO
Monitoring/Data Analysis Workgroup, power point presentation
included in the docket.
---------------------------------------------------------------------------
For the first regional haze SIPs that were due by December 17,
2007, ``baseline visibility conditions'' were the starting points for
assessing ``current'' visibility impairment. Baseline visibility
conditions represent the five-year averages of the degree of visibility
impairment for the 20 percent least impaired days and the 20 percent
most impaired days for each calendar year from 2000 to 2004. Using
monitoring data for 2000 through 2004, states are required to calculate
the average degree of visibility impairment for each Class I area,
based on the average of annual values over the five-year period. The
comparison of initial baseline visibility conditions to natural
visibility conditions indicates the amount of improvement necessary to
attain natural visibility, while the future comparison of baseline
conditions to the then current conditions will indicate the
[[Page 2010]]
amount of progress made. In general, the 2000-2004 baseline period is
considered the time from which improvement in visibility is measured.
3. Best Available Retrofit Technology
Section 169A of the CAA directs 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) of the CAA requires states
to revise their SIPs to contain such measures as may be necessary to
make reasonable progress towards the natural visibility goal, including
a requirement that certain categories of existing major stationary
sources \29\ built between 1962 and 1977 procure, install, and operate
the ``Best Available Retrofit Technology'' as determined by the state.
Under the RHR, states are directed to conduct BART determinations for
such ``BART-eligible'' sources that may be anticipated to cause or
contribute to any visibility impairment in a Class I area. Rather than
requiring source-specific BART controls, states also have the
flexibility to adopt an emissions trading program or other alternative
program as long as the alternative provides greater reasonable progress
towards improving visibility than BART.
---------------------------------------------------------------------------
\29\ See 42 U.S.C. 7491(g)(7) (listing the set of ``major
stationary sources'' potentially subject-to-BART).
---------------------------------------------------------------------------
On July 6, 2005, EPA published the ``Guidelines for BART
Determinations Under the Regional Haze Rule'' at appendix Y to 40 CFR
part 51 (hereinafter referred to as the ``BART Guidelines'') to assist
states in determining which of their sources should be subject to the
BART requirements and in determining appropriate emission limits for
each applicable source.\30\ In making a BART determination for a fossil
fuel-fired electric generating plant with a total generating capacity
in excess of 750 megawatts (MW), a state must use the approach set
forth in the BART Guidelines. A state is encouraged, but not required,
to follow the BART Guidelines in making BART determinations for other
types of sources. Regardless of source size or type, a state must meet
the requirements of the CAA and our regulations for selection of BART,
and the state's BART analysis and determination must be reasonable in
light of the overarching purpose of the regional haze program.
---------------------------------------------------------------------------
\30\ 70 FR 39104, 39104 (July 6, 2005).
---------------------------------------------------------------------------
The process of establishing BART emission limitations can be
logically broken down into three steps: First, states identify those
sources that meet the definition of ``BART-eligible source'' set forth
in 40 CFR 51.301; \31\ second, states determine which of such sources
``emits any air pollutant which may reasonably be anticipated to cause
or contribute to any impairment of visibility in any such area'' \32\
(a source that fits this description is ``subject-to-BART''); and
third, for each source subject-to-BART, states then identify the best
available type and level of control for reducing emissions.
---------------------------------------------------------------------------
\31\ 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 prior to 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.
\32\ 42 U.S.C. 7491(b)(2)(A).
---------------------------------------------------------------------------
States must address all visibility-impairing pollutants emitted by
a source in the BART determination process. The most significant
visibility impairing pollutants are SO2, NOX, and
PM. EPA has stated that states should use their best judgment in
determining whether VOC or NH3 compounds impair visibility
in Class I areas.
Under the BART Guidelines, states may select an exemption threshold
value for their BART modeling, below which a BART-eligible source would
not be expected to cause or contribute to visibility impairment in any
Class I area. The state must document this exemption threshold value in
the SIP and must state the basis for its selection of that value. Any
source with emissions that model above the threshold value would be
subject to a BART determination review. The BART Guidelines acknowledge
varying circumstances affecting different Class I areas. States should
consider the number of emission sources affecting the Class I areas at
issue and the magnitude of the individual sources' impacts. Any
exemption threshold set by the state should not be higher than 0.5
dv.\33\
---------------------------------------------------------------------------
\33\ 40 CFR part 51, appendix Y, Sec. III.A.1.
---------------------------------------------------------------------------
In their SIPs, states must identify the sources that are subject-
to-BART and document their BART control determination analyses for such
sources. In making their BART determinations, section 169A(g)(2) of the
CAA requires that states consider the following factors when evaluating
potential control technologies: (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.
A regional haze SIP must include source-specific BART emission
limits and compliance schedules for each source subject-to-BART. Once a
state has made its BART determination, the BART controls must be
installed and in operation as expeditiously as practicable, but no
later than five years after the date of EPA approval of the regional
haze SIP.\34\ As noted previously, the RHR allows states to implement
an alternative program in lieu of BART so long as the alternative
program can be demonstrated to achieve greater reasonable progress
toward the national visibility goal than would BART.
---------------------------------------------------------------------------
\34\ 42 U.S.C. 7491(g)(4); 40 CFR 51.308(e)(1)(iv).
---------------------------------------------------------------------------
4. Monitoring, Recordkeeping and Reporting
The CAA requires that SIPs, including the regional haze SIP,
contain elements sufficient to ensure emission limits are practically
enforceable. CAA section 110(a)(2) requires in part that the
monitoring, recordkeeping and reporting (MRR) provisions of states'
SIPs must include enforceable emission limitations, control measures,
and compliance timeframes. It also requires SIPs to provide for
enforcement of these measures, installation, maintenance, and
replacement of equipment, emissions monitoring, periodic emissions
reports and availability of emissions reports for public inspection.
Accordingly, 40 CFR part 51, subpart K, Source Surveillance,
requires the SIP to provide for monitoring the status of compliance
with the regulations in it, including ``[p]eriodic testing and
inspection of stationary sources,'' \35\ and ``legally enforceable
procedures'' for recordkeeping and reporting.\36\ Furthermore, 40 CFR
part 51, appendix V, Criteria for Determining the Completeness of Plan
Submissions, states in section 2.2 that complete SIPs contain: ``(g)
Evidence that the plan contains emission limitations, work practice
standards and recordkeeping/reporting requirements, where necessary, to
ensure emission levels''; and ``(h) Compliance/enforcement strategies,
including how compliance will be determined in practice.''
---------------------------------------------------------------------------
\35\ 40 CFR 51.212(a).
\36\ 40 CFR 51.211.
---------------------------------------------------------------------------
5. Consultation With States and Federal Land Managers (FLMs)
The RHR requires that states consult with FLMs before adopting and
submitting their SIPs.\37\ States must
[[Page 2011]]
provide FLMs an opportunity for consultation, in person and at least 60
days prior to holding any public hearing on the SIP. This consultation
must include the opportunity for the FLMs to discuss their assessments
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, five-year progress reports,
and the implementation of other programs having the potential to
contribute to impairment of visibility in Class I areas.
---------------------------------------------------------------------------
\37\ 40 CFR 51.308(i).
---------------------------------------------------------------------------
C. Requirements for Regional Haze SIPs Submitted Under 40 CFR 51.309
The following is a summary and basic explanation of the regulations
covered under section 51.309 of the RHR that are addressed in this
notice.\38\
---------------------------------------------------------------------------
\38\ Utah addressed some of the requirements of 40 CFR 51.309 in
2008 and 2011 SIP submissions. EPA took final action on some of the
provisions in the 2008 and 2011 SIP submissions in earlier notices.
See 40 CFR 51.309 for a complete listing of the regulations under
which the 2008 and 2011 SIP submissions were evaluated.
---------------------------------------------------------------------------
1. Projection of Visibility Improvement
For each of the 16 Class I areas located on the Colorado Plateau,
the SIP must include a projection of the improvement in visibility
expressed in deciviews.\39\ An explanation of the deciview metric is
provided in section III.C.2. States need to show the projected
visibility improvement for the best and worst 20 percent days through
the year 2018, based on the application of all section 309 control
strategies.
---------------------------------------------------------------------------
\39\ 40 CFR 51.309(d)(2).
---------------------------------------------------------------------------
2. Stationary Source Reductions
a. Sulfur Dioxide Emission Reductions
Rather than requiring source-specific BART controls as explained
previously in section III.C.4, states have the flexibility to adopt an
emissions trading program or other alternative program as long as the
alternative provides greater reasonable progress than would be achieved
by the application of BART pursuant to 40 CFR 51.308(e)(2). Under 40
CFR 51.309, states can satisfy the SO2 BART requirements by
adopting SO2 emission milestones and a backstop trading
program.\40\ Under this approach, states must establish declining
SO2 emission milestones for each year of the program through
2018. The milestones must be consistent with the GCVTC's goal of 50 to
70 percent reduction in SO2 emissions by 2040.
---------------------------------------------------------------------------
\40\ 40 CFR 51.309(d)(4).
---------------------------------------------------------------------------
Pursuant to 40 CFR 51.309(d)(4)(ii) through (iv), states must
include requirements in the SIP that allow states to determine whether
the milestone has been exceeded. These requirements include
documentation of the baseline emission calculation, monitoring,
recordkeeping, and reporting of SO2 emissions, and
provisions for conducting an annual evaluation to determine whether the
milestone has been exceeded. SIPs must also contain requirements for
implementing the backstop trading program in the event that the
milestone is exceeded and the program is triggered.\41\
---------------------------------------------------------------------------
\41\ 40 CFR 51.309(d)(4)(v).
---------------------------------------------------------------------------
The WRAP, in conjunction with EPA, developed a model for a backstop
trading program. In order to ensure consistency between states, states
opting to participate in the 309 program needed to adopt rules that are
substantively equivalent to the model rules for the backstop trading
program to meet the requirements of 40 CFR 51.309(d)(4). The trading
program must also be implemented no later than 15 months after the end
of the first year that the milestone is exceeded, require that sources
hold allowances to cover their emissions, and provide a framework,
including financial penalties, to ensure that the 2018 milestone is
met.
b. Provisions for Stationary Source Emissions of Nitrogen Oxides and
Particulate Matter
Pursuant to 40 CFR 51.309(d)(4)(vii), a section 309 SIP must
contain any necessary long term strategies and BART requirements for PM
and NOX. These requirements, including the process for
conducting BART determinations either based on the consideration of the
five statutory factors or based on an alternative program, are
explained previously in section III.C.4 and in section III.E,
respectively.
D. General Requirements for PM10 and NOX
Alternative Programs Under the Regional Haze Rule and the ``Better-
Than-BART Demonstration''
States opting to submit an alternative program must meet
requirements under 40 CFR 51.308(e)(2) and (e)(3). These requirements
for alternative programs relate to the ``better-than-BART'' test and
fundamental elements of any alternative program.
In order to demonstrate that the alternative program achieves
greater reasonable progress than source-specific BART, a state must
demonstrate that its SIP meets the requirements in 40 CFR
51.308(e)(2)(i) through (v). States submitting section 309 SIPs or
other alternative programs are required to list all BART-eligible
sources and categories covered by the alternative program. States are
then required to determine which BART-eligible sources are ``subject-
to-BART.'' The SIP must provide an analysis of the best system of
continuous emission control technology available and the associated
reductions for each source subject-to-BART covered by the alternative
program, or what is termed a ``BART benchmark.'' Where the alternative
program has been designed to meet requirements other than BART, states
may use simplifying assumptions in establishing a BART benchmark.
Pursuant to 40 CFR 51.308(e)(2)(i)(E), the State must also provide
a determination that the alternative program achieves greater
reasonable progress than BART under 40 CFR 51.308(e)(3) or otherwise
based on the clear weight of evidence. 40 CFR 51.308(e)(3), in turn,
provides a specific test for determining whether the alternative
achieves greater reasonable progress than BART. If the distribution of
emissions for the alternative program is not substantially different
than for BART, and the alternative program results in greater emission
reductions, then the alternative program may be deemed to achieve
greater reasonable progress. If the distribution of emissions is
significantly different, the differences in visibility between BART and
the alternative program, must be determined by conducting dispersion
modeling for each impacted Class I area for the best and worst 20
percent of days. The modeling would demonstrate ``greater reasonable
progress'' if both of the two following criteria are met: (1)
Visibility does not decline in any Class I area, and (2) there is
overall improvement in visibility when comparing the average
differences between BART and the alternative program over all of the
affected Class I areas.
Alternately, pursuant to 40 CFR 51.308(e)(2) States may show that
the BART alternative achieves greater reasonable progress than the BART
benchmark ``based on the clear weight of evidence'' determinations,
which
``attempt to make use of all available information and data which
can inform a
[[Page 2012]]
decision while recognizing the relative strengths and weaknesses of
that information in arriving at the soundest decision possible.
Factors which can be used in a weight of evidence determination in
this context may include, but not be limited to, future projected
emissions levels under the program as compared to under BART, future
projected visibility conditions under the two scenarios, the
geographic distribution of sources likely to reduce or increase
emissions under the program as compared to BART sources, monitoring
data and emissions inventories, and sensitivity analyses of any
models used. This array of information and other relevant data may
be of sufficient quality to inform the comparison of visibility
impacts between BART and the alternative program. In showing that an
alternative program is better than BART and when there is confidence
that the difference in visibility impacts between BART and the
alternative scenarios are expected to be large enough, a weight of
evidence comparison may be warranted in making the comparison. The
EPA will carefully consider the evidence before us in evaluating any
SIPs submitted by States employing such an approach.'' \42\
---------------------------------------------------------------------------
\42\ 71 FR 60612, 60622 (Oct. 13, 2006).
Finally, in promulgating the final regional haze program
requirements and responding to concerns regarding ``impermissibly
vague'' language in Sec. 51.308(e)(3) that would allow a State to
``approve alternative measures that are less protective than BART,'' we
explained that ``[t]he State's discretion in this area is subject to
the condition that it must be reasonably exercised and that its
decisions be supported by adequate documentation of its analyses.''
\43\
---------------------------------------------------------------------------
\43\ 71 FR 60612, 60621.
---------------------------------------------------------------------------
Under 40 CFR 51.308(e)(2)(iii) and (iv), all emission reductions
for the alternative program must take place by 2018, and all the
emission reductions resulting from the alternative program must be
surplus to those reductions resulting from measures adopted to meet
requirements of the CAA as of the baseline date of the SIP. Pursuant to
40 CFR 51.309(e)(2)(v), states have the option of including a provision
that the emissions trading program or other alternative measure include
a geographic enhancement to the program to address the requirement
under 40 CFR 51.302(c) related to BART for reasonably attributable
visibility impairment from the pollutants covered under the emissions
trading program or other alternative measure.
E. Summary of State Regional Haze Submittals and EPA Actions
1. 2008 and 2011 Utah RH SIPs
On May 26, 2011, the Governor of the State of Utah submitted to EPA
a Regional Haze SIP under 40 CFR 51.309 of the RHR (``2011 Utah RH
SIP''). This submittal included BART determinations for NOX
and PM10 at Utah's four subject-to-BART sources:
PacifiCorp's Hunter Units 1 and 2 and Huntington Units 1 and 2. All
four units are tangentially fired fossil fuel fired EGUs each with a
net generating capacity of 430 MW, permitted to burn bituminous coal.
This submittal also included a backstop trading program under 40 CFR
51.309 intended to meet the requirement for controlling SO2
by establishing a cap on emissions. The trading program covers Utah,
Wyoming, New Mexico and the City of Albuquerque.
Utah also submitted SIPs on December 12, 2003, August 8, 2004 and
September 9, 2008, to meet the requirements of the RHR. These
submittals were, for the most part, superseded and replaced by the May
26, 2011 submittal as further explained in the next section discussing
our action on these submittals.
2. 2012 EPA Action on 2011 and 2008 Utah RH SIPs
On December 14, 2012, EPA partially approved and partially
disapproved the 2011 Utah RH SIP.\44\ We approved all sections of the
2011 Utah RH SIP as meeting the requirements of 40 CFR 51.309, with the
exception of the requirements under 40 CFR 51.309(d)(4)(vii) pertaining
to NOX and PM10 BART. EPA's partial disapproval
action was based on the following: (1) Utah did not take into account
the five statutory factors in its BART analyses for NOX and
PM10; and (2) the 2011 Utah RH SIP did not contain the
provisions necessary to make the BART limits practically enforceable as
required by section 110(a)(2) of the CAA and 40 CFR 51, appendix V.\45\
---------------------------------------------------------------------------
\44\ 77 FR 74355, 74357 (Dec. 14, 2012).
\45\ Id.
---------------------------------------------------------------------------
We also approved two sections of the 2008 Utah RH SIP.
Specifically, we approved UAR R307-250--Western Backstop Sulfur Dioxide
Trading Program and R307-150--Emission Inventories. We took no action
on the rest of the 2008 submittal as the 2011 submittal superseded and
replaced the remaining sections of the 2008 submittal. We also took no
action on the December 12, 2003 and August 8, 2004 submittals as these
were superseded by the 2011 submittal.
On November 8, 2011, we separately proposed approval of Section G--
Long-Term Strategy for Fire Programs of the May 26, 2011 submittal and
finalized our approval of that action on January 18, 2013.\46\
---------------------------------------------------------------------------
\46\ 78 FR 4071, 4072 (Jan. 18, 2013).
---------------------------------------------------------------------------
3. 2013 Litigation
In 2013, conservation groups sued EPA in the U.S. Court of Appeals
for the Tenth Circuit on our approval of the SO2 backstop
trading program as an alternative to BART. On October 21, 2014, the
court upheld EPA's finding that the trading program was better than
BART.\47\
---------------------------------------------------------------------------
\47\ Wildearth Guardians v. United States EPA, 728 F.3d 1075,
1083-84 (10th Cir. 2013).
---------------------------------------------------------------------------
4. 2015 Utah RH SIPs
On June 4, 2015, the Governor of the State of Utah submitted to EPA
a revision to its Regional Haze SIP under 40 CFR 51.309 of the RHR
(``June 2015 Utah RH SIP''), specifically to address the requirements
under 40 CFR 51.309(d)(4)(vii) pertaining to NOX and
PM10 BART. Utah developed the June 2015 Utah RH SIP in
response to EPA's December 14, 2012 partial disapproval of the 2011
Utah RH SIP. The June 2015 Utah RH SIP evolved from a draft SIP on
which Utah sought public comment in October 2014. After receiving
extensive public comments, Utah decided to pursue a BART alternative
(``Utah BART Alternative,'' ``BART Alternative,'' or ``Alternative'')
under 40 CFR 51.308(e)(2) that takes credit for early NOX
reductions due to combustion controls installed at PacifiCorp's Hunter
and Huntington power plants in addition to NOX,
SO2, and PM10 reductions from the August 2015
retirement of PacifiCorp's nearby Carbon power plant. The June 2015
Utah RH SIP also includes measures to make the SIP requirements
practically enforceable and includes additional information pertaining
to the PM10 BART determinations for Hunter and Huntington to
address deficiencies identified by EPA in our December 2012 partial
disapproval.
On October 20, 2015, Utah submitted to EPA an additional revision
to its Regional Haze SIP under 40 CFR 51.309 of the RHR (``October 2015
Utah RH SIP''). This SIP includes an enforceable commitment to provide
an additional SIP revision by mid-March 2018 to address concerns raised
in public comments that the State would be double counting certain
emissions reductions under the Utah BART Alternative in respect to
milestone reporting for the SO2 backstop trading program.
Sections 110(a)(2) and 110(l) of the CAA require that a state
provide reasonable notice and public hearing
[[Page 2013]]
before adopting a SIP revision and submitting it to us. Utah, after
providing notice, accepted comments on the June 2015 Utah RH SIP in
April 2015 and accepted comments on the October 2015 Utah RH SIP in
mid-August through mid-September 2015. Following the comment period and
legal review by the Utah Attorney General's Office, the Utah Air
Quality Board adopted the June 2015 Utah RH SIP on June 3, 2015 and the
October 2015 Utah RH SIP on October 7, 2015. The Governor submitted the
SIP revisions to EPA on June 4, 2015 and October 20, 2015.
IV. Utah's Regional Haze SIP
A. Summary of Elements Under EPA's Previous Actions Upon Which We Are
Relying
Several SIP elements that we previously approved in our December
2012 final rule and upon which we are relying in our current action
include the following:
1. Affected Class I Areas
Utah provided two maps in Section XX of its 2011 RH SIP, one
showing the locations of the 16 Class I areas on the Colorado Plateau
and one showing the locations of the five in Utah (Arches National
Park, Bryce Canyon National Park, Canyonlands National Park, Capitol
Reef National Park, and Zion National Park).\48\ Utah also provided a
comparison of the monitored 2000-2004 baseline visibility conditions in
deciviews for the 20 percent best and 20 percent worst days to the
projected visibility improvement for 2018 for the 16 Class I areas.\49\
---------------------------------------------------------------------------
\48\ See Utah Regional Haze State Implementation Plan, Sec.
XX.B.8, pp. 8-9 (Figures 1 and 2) (2011).
\49\ See id., at Sec. XX.K.2, p. 116 (Table 24).
---------------------------------------------------------------------------
We determined that the State's SIP satisfies the requirements of 40
CFR 51.309(d)(2) for this element in our December 14, 2012 rulemaking.
2. BART-Eligible Sources
Pursuant to 40 CFR 51.308(e)(2)(i)(A), the 2011 Utah RH SIP listed
the BART-eligible sources covered by the backstop trading program (see
Table 1). The State identified the following BART-eligible sources in
Utah: PacifiCorp Hunter Units 1 and 2 and PacifiCorp Huntington Units 1
and 2.
PacifiCorp's Hunter Power Plant (Hunter), is located in Castle
Dale, Utah and consists of three electric utility steam generating
units. Of the three units, only Units 1 and 2 are subject to BART.
Hunter Units 1 and 2 have a nameplate generating capacity of 488.3 MW
each.\50\ The boilers are tangentially fired pulverized coal boilers,
burning bituminous coal from the Deer Creek Mine in Utah.
---------------------------------------------------------------------------
\50\ See U.S. Energy Information Administration, Electric
Generating Capacity for 2011 (taken from Form EIA-860). See ``EIA
existing generating units 2011.xls'' spreadsheet in the docket.
---------------------------------------------------------------------------
PacifiCorp's Huntington Power Plant (Huntington), is located in
Huntington City, Utah, and consists of two electric utility steam
generating units. Huntington Units 1 and 2 have a nameplate generating
capacity of 498 MW each.\51\ The boilers are tangentially fired
pulverized coal boilers, burning bituminous coal from the nearby Deer
Creek Mine.
---------------------------------------------------------------------------
\51\ Id.
---------------------------------------------------------------------------
We determined that the State's SIP satisfies the requirements of 40
CFR 51.309(e)(2)(i)(A) in our December 14, 2012 rulemaking.
3. Sources Subject-to-BART
Pursuant to 40 CFR 51.308(e)(2)(i)(B), the 2011 Utah RH SIP
described the State's source modeling that determined which of the
BART-eligible sources within Utah cause or contribute to visibility
impairment and are thus subject-to-BART (more information on subject-
to-BART sources and modeling can be found in Section XX.D.6 of the 2011
Utah RH SIP and section V.F of our May 16, 2012 proposed rulemaking).
Table 1 shows Utah's BART-eligible sources covered by the 309
SO2 backstop program, Hunter Units 1 and 2, and Huntington
Units 1 and 2, and indicates that all are subject-to-BART.
We determined that the State's SIP satisfies the requirements of 40
CFR 51.308(e)(2)(i)(B) in our December 14, 2012 rulemaking.
Table 1--Subject-to-BART Status for Utah's Section 309 BART-Eligible Sources
--------------------------------------------------------------------------------------------------------------------------------------------------------
Generating
Company Source Unit ID Service BART Category capacity Coal type Boiler type Subject- to-
date (MW) BART?
--------------------------------------------------------------------------------------------------------------------------------------------------------
PacifiCorp................... Hunter.......... 1 1978 Fossil Fuel EGU. 430 Bituminous...... Tangential...... Yes.
PacifiCorp................... Hunter.......... 2 1980 Fossil Fuel EGU. 430 Bituminous...... Tangential...... Yes.
PacifiCorp................... Huntington...... 1 1977 Fossil Fuel EGU. 430 Bituminous...... Tangential...... Yes.
PacifiCorp................... Huntington...... 2 1974 Fossil Fuel EGU. 430 Bituminous...... Tangential...... Yes.
--------------------------------------------------------------------------------------------------------------------------------------------------------
We note that Section XX.D.6 in the June 2015 Utah RH SIP supersedes
Section XX.D.6 in the 2011 Utah RH SIP and that some reformatting
occurred. As Utah did not make substantive revisions to the SIP
provisions addressing BART-eligible sources and subject-to-BART
sources, XX.D.6.b and XX.D.6.c, in the 2011 SIP, we are not proposing
any additional action on these provisions in this preamble.
B. Summary of Utah's BART Alternative and PM10 BART SIP Revision
Utah's June 2015 RH SIPs include the following SIP provisions:
Revised R307-110-17, General Requirements: State
Implementation Plan. Section IX, Control Measures for Area and Point
Sources, Part H, Emissions Limits (incorporates by reference most
recently amended SIP Section IX, Part H into state rules)
Revised R307-110-28, General Requirements: State
Implementation Plan, Regional Haze (incorporates by reference most
recently amended SIP Section XX into state rules)
Revised SIP Section XX.D.6 Regional Haze. Long-Term
Strategy for Stationary Sources. Best Available Retrofit Technology
(BART) Assessment for NOX and PM (supersedes Section XX.D.6
in the 2011 Utah RH SIP)
New SIP Section IX.H.21 General Requirements: Control
Measures for Area and Point Sources, Emission Limits and Operating
Practices, Regional Haze Requirements
New SIP Section IX.H.22 Source Specific Emission
Limitations: Regional Haze Requirements, Best Available Retrofit
Technology.
The June 2015 Utah RH SIP, including the five SIP revisions listed
previously, consists of the following three components: (1) a
NOX BART alternative that includes NOX and
SO2, and PM10 emission reductions from
[[Page 2014]]
Hunter Units 1-3, Huntington Units 1 and 2, and Carbon Units 1 and 2
and PM10 emission reductions from Carbon Units 1 and 2; (2)
BART determinations for PM10 at Hunter Units 1 and 2 and
Huntington Units 1 and 2 based on a streamlined analysis; and (3)
monitoring, recordkeeping and reporting requirements for the Utah BART
Alternative and PM10 BART emission limits to make the SIP
requirements practically enforceable. The emission limits in the June
2015 Utah RH SIP are provided in Table 2. We further explain the three
components of the SIP.
Table 2--Emission Limits and Shutdown in Utah's BART Alternative and PM10 SIP\1\
----------------------------------------------------------------------------------------------------------------
PM10 Limit \2\ (lb/ NOX Limit \3\ (lb/
Source Unit MMBtu, three-run test MMBtu, 30-Day SO2 Limit
average) Rolling Average)
----------------------------------------------------------------------------------------------------------------
Hunter............................ 1 0.015................ 0.26................ NA.
2............................... 2 0.015................ 0.26................ NA.
3 NA................... 0.34................ NA.
Huntington........................ 1 0.015................ 0.26................ NA.
2 0.015................ 0.26................ NA.
Carbon............................ 1 Shutdown by August Shutdown by August Shutdown by August
15, 2015. 15, 2015. 15, 2015.
2 Shutdown by August Shutdown by Shutdown by August
15, 2015. August15, 2015. 15, 2015.
----------------------------------------------------------------------------------------------------------------
\1\ Obtained from the June 2015 Utah RH SIP, Section IX.H.22.
\2\ Based on annual stack testing.
\3\ Based on continuous emission monitoring system (CEMS) measurement.
1. Utah BART Alternative
Utah has opted to establish an alternative measure for
NOX under 40 CFR 51.308(e)(2). The State compared the Utah
BART Alternative against a BART Benchmark of selective catalytic
reduction (SCR) on all four BART units at Hunter and Huntington (Units
1 and 2 at both plants). Utah's BART Alternative consists of the
shutdown of Carbon Units 1 and 2 and the installation of upgraded
NOX combustion controls (new low-NOX burners
[LNB] and overfire air [OFA]) on Hunter Unit 3 (all non-BART units).
The Utah BART Alternative also includes the NOX reductions
from installation of upgraded combustion controls (new LNB and
separated overfire air [SOFA]) at Hunter Units 1 and 2 and Huntington
Units 1 and 2 (all BART units). The BART Benchmark includes the four
BART units with combustion controls and SCR, Carbon's baseline
emissions, and Hunter Unit 3's emissions with original combustion
controls. The Utah BART Alternative is generally described in SIP
Section XX.D.6 with a detailed demonstration included in Chapter 1 of
Utah's Technical Support Document (TSD) to support the State's
assertion that the alternative achieves greater reasonable progress
than BART. The State's demonstration is also described in more detail
in section IV.C.
A summary of the State's estimates of emissions for the Utah BART
Alternative and the BART Benchmark is provided in Table 3. EPA
developed a summary of the emissions reductions based on Utah's
emission estimates and this is presented in Table 4.
Utah indicated that PacifiCorp announced plans to shut down the
Carbon Power Plant in 2015 due to the high cost to control mercury to
meet the requirements of EPA's Mercury and Air Toxics Standards
(MATS).\52\ The State noted that the MATS rule was finalized in 2011,
and the Utah RH SIP contains the requirement for the Carbon Power Plant
to shut down in August 2015. Therefore, the emission reductions occur
after the 2002 base year for Utah's RH SIP and thus, Utah asserts, the
reductions may be considered as part of an alternative strategy under
40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------
\52\ Utah Regional Haze State Implementation Plan, p. 7 (TSD
Chapter 1) (2011).
---------------------------------------------------------------------------
2. PM10 BART Determinations
Utah included a streamlined analysis for PM10 BART
determinations in accordance with section D.9 of the BART Guidelines
for the BART units at Hunter and Huntington in the SIP TSD in Chapter
1, Section III and referenced this analysis in SIP Section XX.D.6. In
the TSD, Utah summarized the BART analysis submitted by PacifiCorp in
an August 5, 2014 report.\53\
---------------------------------------------------------------------------
\53\ For PacifiCorp BART analyses reports, see TSD Chapter 2 of
the SIP.
---------------------------------------------------------------------------
PacifiCorp's analysis identified three available technologies:
Upgraded ESP and flue gas conditioning (0.040 lb/MMBtu); polishing
fabric filter (0.015 lb/MMBtu); and replacement fabric filter (0.015
lb/MMBtu). The 2008 Utah RH SIP and BART determination had required
PacifiCorp to install a fabric filter baghouse with a PM10
emission limit of 0.015 lb/MMBtu at the Hunter and Huntington BART
units. Utah staff reviewed PacifiCorp's 2012 analysis and determined
that the baghouse technology required in 2008 is still the most
stringent technology available and that 0.015 lb/MMBtu represents the
most stringent emission limit. Utah cited EPA's BART Guidelines and
regional haze actions in Colorado, Wyoming, North Dakota and Montana to
support these assertions.
Utah determined that the PM10 BART emission limit for
Hunter Units 1 and 2 and Huntington Units 1 and 2 was 0.015 lb/MMBtu
based on a three-run test average. Utah noted that because the most
stringent technology is in place at these units and that the
PM10 emission limits have been made enforceable in the SIP,
no further analysis was required.
3. Monitoring, Recordkeeping and Reporting
To address EPA's partial disapproval of the 2011 Utah RH SIP for
lack of enforceable measures and monitoring, recordkeeping and
reporting requirements for the Utah BART Alternative and the
PM10 BART determinations, Utah added two new subsections to
SIP Sections IX, General H.21 and 22. Under H.21, Utah has detailed
general requirements for sources subject to its regional haze program.
Under H.22, Utah has listed source-specific regional haze requirements
for Hunter, Huntington and Carbon.
Specifically, under H.21, Utah added a new definition for boiler
operating day. Utah noted that state rules R307-107-1 and R307-107-2
(applicability, timing and reporting of breakdowns) apply to sources
subject to regional haze requirements under H.22. Utah required that
information used to determine compliance shall be recorded for all
periods when the source is in operation, and that such records shall be
kept for a minimum of five years. Under H.21, Utah specified that
emission limitations listed in H.22 shall apply at all times
[[Page 2015]]
and identified stack testing requirements to show compliance with those
emission limitations. Finally, under H.21, Utah also specified the
requirements for continuous emission monitoring by listing the
requirements and cross-referencing the State's rule for continuous
emission monitoring system requirements, R307-170 as well as 40 CFR
part 13 and 40 CFR part 60, appendix B--Performance Specifications.
Utah included the requirements to calculate hourly average
NOX concentrations for any hour in which fuel is combusted
and a new 30-day rolling average emission rate at the end of each
boiler operating day. Utah also noted that the hourly average
NOX emission rate is valid only if the minimum number of
data points specified in R307-170 is acquired for both the pollutant
concentration monitor and diluent monitor.
Under H.21, Utah did not provide for reporting of violations of
PM10 emissions limitations for instances other than
breakdowns (e.g., stack test violations). However, the State provided a
commitment letter on December 10, 2015 to address this deficiency with
a SIP revision within one year of EPA's final action on the June 4,
2015 RH SIP.\54\
---------------------------------------------------------------------------
\54\ Letter from Department of Environmental Quality, State of
Utah to EPA, DAQP-120-15 (Dec. 10, 2015).
---------------------------------------------------------------------------
Under H.22, Utah provided the NOX and PM10
emission limitations for Hunter Units 1 through 3 and Huntington Units
1 and 2, a requirement to perform annual stack testing for
PM10, and a requirement to measure NOX via
continuous emission monitoring for the sources covered under the Utah
BART Alternative. Under H.22, Utah also listed the enforceable
conditions related to closing Carbon Units 1 and 2 by August 15, 2015
including PacifiCorp's and Utah's notification and permit rescission
obligations.
C. Summary of Utah's Demonstration for Alternative Program
As discussed previously in background section III.A, a state may
opt to implement an alternative measure rather than to require sources
subject to BART to install, operate, and maintain BART. Utah has
included the following information in its June and October 2015 RH SIPs
to address the regulatory criteria for an alternative program:
1. A List of All BART-Eligible Sources Within the State
Pursuant to 40 CFR 51.308(e)(2)(i)(A) and (B), the SIP must include
a list of all BART-eligible sources within the State. Utah included a
list of BART-eligible sources and noted the following sources are all
covered by the alternative program:
PacifiCorp Hunter, Unit 1
PacifiCorp Hunter, Unit 2
PacifiCorp, Huntington, Unit 1
PacifiCorp, Huntington, Unit 2
Utah provided the same list of BART-eligible sources in the 2011 RH
SIP. We determined that the State's SIP satisfies the requirements of
40 CFR 51.309(e)(2)(i)(A) in our December 14, 2012 rulemaking.
2. A List of All BART-Eligible Sources and All BART Source Categories
Covered by the Alternative Program
Pursuant to 40 CFR 51.308(e)(2)(i)(B), each BART-eligible source in
the State must be subject to the requirements of the alternative
program or have a federally enforceable emission limitation determined
by the State and approved by EPA as meeting BART. In this instance, the
alternative program covers all the BART-eligible sources in the state,
Hunter Units 1 and 2 and Huntington Units 1 and 2, in addition to three
non-BART units, PacifiCorp's Hunter Unit 3 and Carbon Units 1 and 2.
Utah provided the same list of BART sources subject to an
alternative program in the 2011 RH SIP. We determined that the State's
SIP satisfies the requirements of 40 CFR 51.309(e)(2)(i)(B) in our
December 14, 2012 rulemaking.
3. Analysis of BART and Associated Emission Reductions Achievable
Pursuant to 40 CFR 51.308(e)(2)(i)(C), the SIP must include an
analysis of BART and associated emission reductions at Hunter and
Huntington. In the June 2015 Utah RH SIP, the State compared the Utah
BART Alternative to a BART Benchmark that included the most stringent
NOX BART controls, SCR plus new LNBs and SOFA, at the four
BART units.
4. Analysis of Projected Emissions Reductions Achievable Through the
BART Alternative
Pursuant to 40 CFR 51. 308(e)(2)(D), the SIP must include ``[a]n
analysis of the projected emissions reductions achievable through the .
. . alternative measure.'' A summary of the State's estimates of
emissions in tons per year (tpy) for the Utah BART Alternative and the
BART Benchmark is provided in Table 3. A summary of the emissions
reductions based on those emission estimates is presented in Table 4.
---------------------------------------------------------------------------
\55\ Utah Regional Haze State Implementation Plan, Technical
Support Document, Ch. 1 (Reference Table 2) (2015).
Table 3--Estimated Emissions Under Utah's BART Benchmark and the BART Alternative \55\
--------------------------------------------------------------------------------------------------------------------------------------------------------
NOX emissions (tpy) SO2 emissions (tpy) PM10 emissions (tpy) \4\ Combined
---------------------------------------------------------------------------------------------------------------
Units Benchmark Alternative Benchmark Alternative
\2\ \3\ \2\ \3\ Benchmark Alternative Benchmark Alternative
--------------------------------------------------------------------------------------------------------------------------------------------------------
Carbon 1................................ 1,408 0 3,388 0 221 0 5,016 0
Carbon 2................................ 1,940 0 4,617 0 352 0 6,909 0
Hunter 1 \1\............................ 775 3,412 1,529 1,529 169 169 2,473 5,100
Hunter 2................................ 843 3,412 1,529 1,529 169 169 2,541 5,110
Hunter 3................................ 6,530 4,622 1,033 1,033 122 122 7,685 5,777
Huntington 1............................ 809 3,593 1,168 1,168 176 176 2,153 4,937
Huntington 2............................ 856 3,844 1,187 1,187 200 200 2,243 5,231
---------------------------------------------------------------------------------------------------------------
Total............................... 13,161 18,882 14,451 6,446 1,409 836 29,020 26,164
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Hunter 1 controls were installed in the spring of 2014, therefore Hunter 2 actual emissions are used as a surrogate.
\2\ Most stringent NOX rate for BART-eligible units (see email and spreadsheet, ``Attachment to Utah September 16, 2015 email, BART Analysis.pdf'' in
the docket, inadvertently omitted from Utah TSD), 2012-2013 actual emissions Carbon, 2001-2003 actual emissions Hunter 3 (EPA Acid Rain Program).
\3\ Average actual emissions 2012-13 for Hunter and Huntington units, EPA Acid Rain Program.
\4\ Actual emissions for 2012, Utah Department of Air Quality annual inventory.
[[Page 2016]]
Table 4--EPA Summary of Emission Reductions Achievable With the Utah BART Alternative as Compared to the BART
Benchmark
----------------------------------------------------------------------------------------------------------------
Combined emissions for all units (tpy)
Description ---------------------------------------------------
NOX SO2 PM10 Combined
----------------------------------------------------------------------------------------------------------------
BART Benchmark.............................................. 13,161 14,451 1,409 29,020
BART Alternative............................................ 18,882 6,446 836 26,164
Emission Reduction (BART Benchmark minus BART Alternative) -5,721 8,005 573 2,856
\1\........................................................
----------------------------------------------------------------------------------------------------------------
\1\ A negative value indicates the BART Alternative results in more emissions of the specified pollutant in
comparison to the BART Benchmark.
5. A Determination That the Alternative Achieves Greater Reasonable
Progress Than Would Be Achieved Through the Installation and Operation
of BART
Pursuant to 40 CFR 51.308(e)(2)(i)(E), the State must provide a
determination under 40 CFR 51.308(e)(3) or otherwise based on the clear
weight of evidence that the alternative achieves greater reasonable
progress than BART. 40 CFR 51.308(e)(3), in turn, provides two
different tests for determining whether the alternative achieves
greater reasonable progress than BART.
Utah first used the ``greater emission reductions'' test in 40 CFR
51.308(e)(3) to support its assertion that the BART Alternative
achieves greater reasonable progress. In the June 2015 Utah RH SIP, the
State noted that the Hunter, Huntington and Carbon plants are all
located within 40 miles of each other in Central Utah. Utah stated that
because of the close proximity of the three plants, the distribution of
emissions would not be substantially different under the Utah BART
Alternative than under BART. With the alternative measure resulting in
greater aggregate emission reductions by 2,856 tons/year (tpy)
(described in Table 4), Utah asserted that the alternative measure may
be deemed to achieve greater reasonable progress than BART under
51.308(e)(3).
Utah also chose to conduct a weight-of-evidence analysis under
51.308(e)(2) based on emissions from the Hunter, Huntington, and Carbon
power plants and considered the following evidence: \56\
---------------------------------------------------------------------------
\56\ Utah referenced that greater reasonable progress can be
demonstrated using one of two methods: (1) greater emission
reductions than under BART (40 CFR 51.308(e)(3)); or (2) based on
the clear weight of evidence (40 CFR 51.308(e)(2)(i)(E)). Utah
further explained that: As the U.S. Circuit Court of Appeals for the
10th Circuit recently observed, the state is free to choose one
method or the other. WildEarth Guardians v. E.P.A., 770 F.3d 919,
935-37 (10th Cir. 2014). Finally, Utah noted that the court
characterized the former approach as ``quantitative'' and the latter
as ``qualitative,'' and specifically sanctioned the use of
qualitative factors under the clear weight of evidence.
---------------------------------------------------------------------------
a. Annual Emissions Comparison for Visibility-impairing Pollutants
The emissions of visibility-impairing pollutants from both the Utah
BART Alternative and the BART Benchmark, as estimated by the State, are
summarized in Table 3. Compared with the Utah BART Benchmark, the State
projects that the Utah BART Alternative will result in 5,721 tpy more
NOX emissions, 8,005 tpy fewer SO2 emissions and
573 tpy fewer PM10 emissions. Utah also found that the
combined emissions of NOX, SO2 and
PM10 will be 2,856 tpy lower under the Utah BART
Alternative.
b. Improvement in the Number of Days With Significant Visibility
Impairment
Utah provided modeling results to assess the improvement in the
number of days with significant visibility impairment--that is, the
improvement in the number of days with impacts that either cause (> 1.0
dv) or contribute (> 0.5 dv) to visibility impairment. The State
presented this information in a number of ways, including: (1) the
average number of days per year for three years modeled (2001-2003)
with impacts above the cause and contribute thresholds for the nine
affected Class I areas under the BART Alternative as compared to under
the BART Benchmark; and (2) the total number of days for the three
years modeled with impacts above the thresholds for the nine Class I
areas under the two scenarios.\57\
---------------------------------------------------------------------------
\57\ Utah noted that EPA has proposed approval of an Alternative
Measure for the Apache Generating Station in Arizona on similar
``weight of evidence'' grounds. 79 FR 56322, 56327 (Sept. 19, 2014).
Utah also noted that EPA has approved a similar Alternative Measure
in Washington, based in part on a reduction in the number of days of
impairment greater than 0.5 dv and 1.0 dv. 79 FR 33438, 33440-33442
(June 11, 2014).
---------------------------------------------------------------------------
On average for the three years modeled, the Utah BART Alternative
causes visibility impairment (>1.0 dv) on fewer days than the BART
Benchmark (258 days vs. 264 days, for the nine affected Class I areas).
Similarly, on average for the three years modeled, the Utah BART
Alternative also contributes to visibility impairment (>0.5 dv) on
fewer days than the BART Benchmark (441 days vs. 499 days for the nine
affected Class I areas). See Tables 5 and 6.
---------------------------------------------------------------------------
\58\ Utah Regional Haze State Implementation Plan, Technical
Support Document, Ch. 1 (Reference Table 5) (2015).
Table 5--Average (2001-2003) Number of Days >1.0 dv Impact \58\
----------------------------------------------------------------------------------------------------------------
BART BART
Class I area Basecase alternative benchmark
----------------------------------------------------------------------------------------------------------------
Arches.......................................................... 128 68 77
Black Canyon of the Gunnison.................................... 36 10 9
Bryce Canyon.................................................... 19 9 8
Canyonlands..................................................... 141 87 87
Capitol Reef.................................................... 68 42 41
Flat Tops....................................................... 46 13 15
Grand Canyon.................................................... 22 11 10
Mesa Verde...................................................... 40 13 12
Zion............................................................ 11 6 6
-----------------------------------------------
[[Page 2017]]
Total....................................................... 511 258 264
----------------------------------------------------------------------------------------------------------------
Table 6--Average (2001-2003) Number of Days >0.5 dv Impact \59\
----------------------------------------------------------------------------------------------------------------
BART BART
Class I area Basecase alternative benchmark
----------------------------------------------------------------------------------------------------------------
Arches.......................................................... 176 109 130
Black Canyon of the Gunnison.................................... 75 27 34
Bryce Canyon.................................................... 36 17 19
Canyonlands..................................................... 178 131 140
Capitol Reef.................................................... 96 63 65
Flat Tops....................................................... 93 34 44
Grand Canyon.................................................... 38 19 20
Mesa Verde...................................................... 71 32 37
Zion............................................................ 21 10 10
-----------------------------------------------
Total....................................................... 784 441 499
----------------------------------------------------------------------------------------------------------------
As for the total number of days over the course of the three
modeled years, the Utah BART Alternative causes visibility impairment
(> 1.0 dv) on fewer days than the BART Benchmark (775 days vs. 793 days
for the nine affected Class I areas). Similarly, in total for the three
years modeled, the Utah BART Alternative also contributes to visibility
impairment (> 0.5 dv) on fewer days than the BART Benchmark (1,323 days
vs. 1,498 days for the nine affected Class I areas). See Tables 7 and
8.
---------------------------------------------------------------------------
\59\ See id., at Technical Support Document, Ch. 1 (Reference
Table 6).
\60\ See id., at Technical Support Document, Chapter 6.b
(Summary of Visibility Modeling).
Table 7--Total (2001-2003) Number of Days >1.0 dv Impact \60\
----------------------------------------------------------------------------------------------------------------
BART BART
Class I area Basecase alternative benchmark
----------------------------------------------------------------------------------------------------------------
Arches.......................................................... 383 203 230
Black Canyon of the Gunnison.................................... 108 31 28
Bryce Canyon.................................................... 57 26 25
Canyonlands..................................................... 422 260 260
Capitol Reef.................................................... 204 126 124
Flat Tops....................................................... 138 38 44
Grand Canyon.................................................... 67 34 30
Mesa Verde...................................................... 121 40 35
Zion............................................................ 32 17 17
-----------------------------------------------
Total....................................................... 1,532 775 793
----------------------------------------------------------------------------------------------------------------
Table 8--Total (2001-2003) Number of Days >0.5 dv Impact \61\
----------------------------------------------------------------------------------------------------------------
BART BART
Class I area Basecase alternative benchmark
----------------------------------------------------------------------------------------------------------------
Arches.......................................................... 529 327 391
Black Canyon of the Gunnison.................................... 224 81 103
Bryce Canyon.................................................... 107 50 57
Canyonlands..................................................... 533 393 420
Capitol Reef.................................................... 288 188 194
Flat Tops....................................................... 280 101 133
Grand Canyon.................................................... 115 56 59
Mesa Verde...................................................... 213 97 110
Zion............................................................ 63 30 31
-----------------------------------------------
Total....................................................... 2,352 1,323 1,498
----------------------------------------------------------------------------------------------------------------
[[Page 2018]]
c. 98th Percentile Impact (dv)
Utah explained that the only metric it evaluated that showed
greater improvement for the BART Benchmark in comparison to the BART
Alternative was the 98th percentile metric when visibility impacts were
averaged across all Class I areas and meteorological years modeled.
Utah's comparison of the modeled visibility impacts on the 98th
percentile day (8th highest impacted day in a given meteorological
year) for the most impacted year shows that the BART Benchmark would
result in greater visibility improvement at five of the nine Class I
areas, and is better on average across all nine Class I areas (0.11 dv
difference). At two of the most impacted Class I areas, Canyonlands and
Capitol Reef, Utah found that the 98th percentile metric indicates the
BART Benchmark has 0.76 dv and 0.57 dv, respectively, greater
improvement than the Utah BART Alternative. At other Class I areas,
Utah found that the 98th percentile metric indicates that the BART
Alternative provides greater visibility improvement (for example, 0.44
dv at Flat Tops).
---------------------------------------------------------------------------
\61\ See id.
---------------------------------------------------------------------------
Utah noted that because high nitrate values occur primarily in the
winter months, the BART Benchmark achieved greater modeled visibility
improvement on certain winter days with high nitrate impacts. Utah
stated its position that there is greater uncertainty regarding the
effect of NOX reductions on wintertime nitrate values, and
thus on visibility, because past NOX emission reductions
have not resulted in corresponding reductions in monitored nitrate
values during the winter months. Utah noted it has greater confidence
in the visibility improvement due to reductions of SO2
because past reductions have resulted in corresponding reductions in
monitored sulfate values throughout the year.
d. Annual Average Impact (dv)
As modeled by Utah, which used CALPUFF modeling results, the
average annual dv impact is better under the Utah BART Alternative at
five of the nine Class I areas, and is better on average across all the
Class I areas. The average impact was calculated by averaging all daily
modeling results for each year and then calculating a three-year
average from the annual average. Utah's information shows that the BART
Alternative is better than the BART Benchmark by 0.009 dv on average
across all nine Class I areas.
e. 90th Percentile Impact (dv)
Utah's comparison of the modeled visibility impacts at the 90th
percentile (the 110th highest day across three years) dv impact shows
that the Utah BART Alternative is better at seven of the nine Class I
areas and is better averaged both across three years and across nine
Class I areas by 0.006 dv.
f. Timing for the Emissions Reductions
Utah provided the schedule for installation of controls as noted in
Table 9. Utah discussed that NOX reductions at Hunter Units
1 and 2 and Huntington Units 1 and 2 occurred between 2006 and 2014,
earlier than was required by the Regional Haze Rule, providing a
corresponding early and on-going visibility improvement. Utah cited the
2014 10th Circuit Court of Appeals decision regarding the 309 program
to support that such early reductions are properly included as weight
of evidence in the State's analysis.
Table 9--Installation Schedule
------------------------------------------------------------------------
Timing of control installation or
Source/Unit shutdown
------------------------------------------------------------------------
Hunter 1........................ New LNB and SOFA-Spring 2014.
Hunter 2........................ New LNB and SOFA-Spring 2011.
Hunter 3........................ New LNB and OFA-Summer 2008.
Huntington 1.................... New LNB and SOFA-Fall 2010.
Huntington 2.................... New LNB and SOFA-December 2006.
Carbon 1........................ Shutdown August 2015.
Carbon 2........................ Shutdown August 2015.
------------------------------------------------------------------------
The reductions under the Utah BART Alternative are required under
the State SIP by August 2015, as noted in Table 5, providing an early
and on-going visibility benefit as compared to BART.\62\ Installation
and operation of the combustion control upgrades at Hunter and
Huntington were made enforceable under Administrative Orders DAQE-
AN0102370012-08 and DAQE-AN0102380021-10.\63\
---------------------------------------------------------------------------
\62\ Conforming permit amendments for the Carbon plant are due
under the SIP by December 15, 2015. Section IX.H.22 of Utah's SIP
requires PacifiCorp to cease operation of Carbon by August 15, 2015,
notify the State of the permanent closure by September 15, 2015, and
request rescission of Operating Permit #700002004 and Approval Order
DAQE-AN0100810005-08 by September 15, 2015. The State is then
required to rescind the operating permit and approval order by
December 15, 2015.
\63\ Copies of Administrative Orders DAQE-AN0102370012-08 and
DAQE-AN0102380021-10 are included in the docket.
---------------------------------------------------------------------------
g. IMPROVE Monitoring Data
Utah's SIP presents sulfate and nitrate monitoring data at the
Canyonlands IMPROVE monitor that shows that ``sulfates are the dominant
visibility impairing pollutant'' \64\ and that sulfate levels have
decreased,\65\ and references similar results at other Class I areas in
the TSD.\66\ Utah also presents data on trends in emissions from EGUs
showing substantial reductions in emissions of both SO2 and
NOX.\67\ Based on these data, Utah indicates it ``has
confidence that the SO2 reductions will achieve meaningful
visibility improvement,'' under the Utah BART Alternative, while ``the
visibility improvement during the winter months due to NOX
reductions is much more uncertain.'' \68\ Utah makes this point even
though nitrate concentrations are highest in the winter, explaining
that while there has been a reduction in NOX, the ammonium
nitrate values do not show similar improvement in the winter
months.\69\ Utah offers several possible explanations for the results,
but does not provide any definitive conclusions.\70\
---------------------------------------------------------------------------
\64\ Utah Regional Haze State Implementation Plan, Technical
Support Document, Ch. 1, p. 12 (2015).
\65\ Id. at p. 15.
\66\ Id. at p. 12.
\67\ Id. at p. 14.
\68\ Id. at p.13.
\69\ Id.
\70\ Id. at pp. 16-19.
---------------------------------------------------------------------------
Utah also presents data on the seasonality of park visitation and
monitoring data for nitrate and sulfates. The data show that the
highest measured nitrate concentrations occur in winter during the
period of lowest park visitation, and that sulfates affect visibility
throughout the year and are the dominant visibility impairing pollutant
from anthropogenic sources during the high visitation period of March
through November. Utah concludes that it has greater confidence that
reductions in SO2 will be reflected in improved visibility
for visitors to the Class I areas, while reductions in NOX
will have a more uncertain benefit for visitors to Class I areas.
h. Energy and Non-Air Quality Benefits
Utah stated that energy and non-air quality environmental impacts
are one of the factors listed in CAA section 169A(g)(2) that must be
considered when determining BART. The State noted that the Utah BART
Alternative would avoid the energy penalty due to operating SCR units.
PacifiCorp included the energy penalty in its BART analysis as part of
the total cost for installing SCR on each of the units. The energy
penalty costs are provided in Table 10.
---------------------------------------------------------------------------
\71\ PacifiCorp quantified the energy penalty associated with
SCR in its August 4, 2014 BART Analysis Update, Appendix A. See id.
at p. 26 (Table 13 presents this information).
[[Page 2019]]
Table 10--SCR Energy Penalty 71
------------------------------------------------------------------------
Energy penalty
Source/unit ---------------------
kW $/year
------------------------------------------------------------------------
Hunter Unit 1..................................... 2,090 494,247
Hunter Unit 2..................................... 2,090 494,247
Huntington Unit 1................................. 2,182 516,098
Huntington Unit 2................................. 2,182 516,098
---------------------
Total......................................... 8,544 2,020,690
------------------------------------------------------------------------
Utah presented additional non-air quality benefits associated with
the closure of the Carbon plant. First, it noted that solid wastes in
the form of fly ash from the electrostatic precipitators and bottom ash
conveyors which clean the residuals from the two steam generating units
(the boilers), would be eliminated. These wastes are currently
landfilled. The Carbon plant also runs water through the boilers as
well as two cooling towers. This uses water and has associated
wastewater discharge. Hauling the ash to the landfill requires
additional fuel use and water or chemical dust suppression for
minimization of fugitive dust. Finally, for maintenance and emergency
purposes, Utah noted that the plant has a number of emergency
generators, fire pumps, and ancillary equipment--all of which must be
periodically operated, tested and maintained--with associated air
emissions, fuel use, painting, and the like. Utah suggests that all of
these non-air quality impacts are reduced as the result of closing the
Carbon plant.
i. Cost
Utah cited PacifiCorp's comments on the State's proposed SIP
revision that the BART Alternative not only produces greater reasonable
progress, including lower emissions and improved visibility, but that
it does so at a significant capital cost savings to PacifiCorp and its
customers as compared to the BART Benchmark. Utah acknowledged that it
did not officially determine the cost of installing SCR on the four
BART units, but that it believed the cost of installing SCR would be
significant. On the other hand, Utah noted that the Carbon Plant has
already been closed due to the high cost of complying with the MATS
rule. Utah explained that the costs to Utah rate payers (and those in
other states served by PacifiCorp) to replace the power generated by
the Carbon Plant have already occurred; there will be no additional
cost to achieve the co-benefit of visibility improvement. As a result,
Utah asserted that the BART Alternative not only achieves better
visibility improvements than would be achieved by requiring SCR as BART
at the four EGUs, but at a significantly lower cost. The State believed
this presents a classic ``win/win'' scenario--the BART Alternative
results in greater reasonable progress that is achieved at a much lower
price compared to SCR. The State also noted that cost is one of the
factors listed in CAA section 169A(g)(2) that should be considered when
determining BART.
6. Requirement That Emission Reductions Take Place During Period of
First Long-Term Strategy
Pursuant to 40 CFR 51.308(e)(2)(iii), the State must ensure that
all necessary emission reductions take place during the period of the
first long-term strategy for regional haze, i.e., by December 31, 2018.
The RHR further provides that, ``[t]o meet this requirement, the State
must provide a detailed description of the . . . alternative measure,
including schedules for implementation, the emission reductions
required by the program, all necessary administrative and technical
procedures for implementing the program, rules for accounting and
monitoring emissions, and procedures for enforcement.'' \72\
---------------------------------------------------------------------------
\72\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------
As noted previously, the Utah SIP revision incorporates the
revisions to R307-110-17, Section IX, Control Measures for Area and
Point Sources, Part H, Emissions Limits, which includes provisions for
implementing the Utah BART Alternative. In addition to the emission
limitations for NOX and PM10, and the requirement
for shutdown of the Carbon Plant listed in Table 2, the SIP includes
compliance dates, operation and maintenance requirements, and
monitoring, recordkeeping, and reporting requirements.
7. Demonstration That Emissions Reductions From Alternative Program
Will Be Surplus
Pursuant to 40 CFR 51.308(e)(2)(iv), the SIP must demonstrate that
the emissions reductions resulting from the alternative measure will be
surplus to those reductions resulting from measures adopted to meet
requirements of the CAA as of the baseline date of the SIP. The
baseline date for regional haze SIPs is 2002.\73\ Utah developed the
2002 baseline inventory in the 2008 RH SIP for regional modeling,
evaluating the impact on Class I areas outside of the Colorado Plateau,
and BART as outlined in EPA Guidance and the July 6, 2005 BART Rule.
Utah noted that 2002 is the baseline inventory that was used by other
states throughout the country when evaluating BART under the provisions
of 40 CFR 51.308 and that any measure adopted after 2002 is considered
``surplus'' under 40 CFR 51.308(e)(2)(iv). Utah referenced other EPA
actions that are consistent with this interpretation.\74\ Utah stated
that the BART Benchmark scenario includes measures required before the
baseline date of the SIP but does not include later measures that are
credited as part of the BART Alternative scenario.
---------------------------------------------------------------------------
\73\ See Memorandum from Lydia Wegman and Peter Tsirigotis, 2002
Base Year Emission Inventory SIP Planning: 8-hr Ozone,
PM2.5, and Regional Haze Programs (Nov. 18, 2002),
available at http://www3.epa.gov/ttnchie1/eidocs/2002baseinven_102502new.pdf.
\74\ 79 FR 33438, 33441-33442 (June 11, 2014); 79 FR 56322,
56328 (Sept. 9, 2014).
---------------------------------------------------------------------------
To address potential concerns with double counting SO2
emissions reductions from the Carbon plant closure under both the 308
and 309 programs, in addition to providing the explanation in the June
2015 SIP (discussed in TSD Chapter 1, Section X), Utah's October 7,
2015 SIP also includes enforceable commitments to address these
concerns. The State explained how the WRAP modeling done to support the
Utah RH backstop trading program SIP included regional SO2
emissions based on the 2018 SO2 milestone and also included
NOX and PM10 emissions from the Carbon plant.
Actual emissions in the three-state region are calculated each year and
compared to the milestones. Utah provided Table 11 to show that in 2011
emissions were below the 2018 milestone (141,849 tpy). Utah noted that
the most recent milestone report for 2013 demonstrates that
SO2 emissions are currently 26 percent lower than the 2018
milestone. Utah stated that the Carbon plant was fully operational in
the years 2011-2013 when the emissions were below the 2018 milestone.
The State noted that the SO2 emission reductions from the
closure of the Carbon plant are surplus to what is needed to meet the
2018 milestone established in Utah's RH SIP.
---------------------------------------------------------------------------
\75\ See Utah Regional Haze State Implementation Plan, Technical
Support Document, Ch. 1 (Reference Table 15) (2015).
[[Page 2020]]
Table 11--SO2 Milestone Trends 75
----------------------------------------------------------------------------------------------------------------
Three-Year
Milestone average SO2 Carbon plant
Year (tpy) emissions \1\ SO2 emissions
(tpy) (tpy)
----------------------------------------------------------------------------------------------------------------
2003............................................................ 303,264 214,780 5,488
2004............................................................ 303,264 223,584 5,642
2005............................................................ 303,264 220,987 5,410
2006............................................................ 303,264 218,499 6,779
2007............................................................ 303,264 203,569 6,511
2008............................................................ 269,083 186,837 5,057
2009............................................................ 234,903 165,633 5,494
2010............................................................ 200,722 146,808 7,462
2011............................................................ 200,722 130,935 7,740
2012............................................................ 200,722 115,115 8,307
2013............................................................ 185,795 105,084 7,702
2014............................................................ 170,868
2015............................................................ 155,940
2016............................................................ 155,940
2017............................................................ 155,940
2018............................................................ 141,849
----------------------------------------------------------------------------------------------------------------
\1\ The three-year average is based on the emissions averaged for the current and two preceding years.
For Hunter Unit 3, Utah also explained that PacifiCorp upgraded the
LNB controls in 2008 and that the upgrade was not required under the
requirements of the CAA as of the 2002 baseline date of the SIP; the
emission reductions from the upgrade are therefore considered surplus
and creditable for the BART Alternative under 40 CFR 51.308(e)(2)(iv).
Utah noted that prior to the 2008 upgrade, the emission rate for Hunter
Unit 2 was 0.46 lb/MMBtu heat input for a 30-day rolling average as
required by Phase II of the Acid Rain Program.\76\
---------------------------------------------------------------------------
\76\ There is a typographical error in Chapter 1, section X.C,
PacifiCorp Hunter Unit 3, p. 31. The reference to Hunter Unit 2
should be Unit 3 based on the section heading as well as confirmed
emission limits in Utah Approval Order DAQE-AN0102370012-08.
---------------------------------------------------------------------------
D. Summary of Utah's Enforceable Commitment SIP Revision
To address potential concerns that Utah would be double counting
SO2 emissions reductions for the Carbon plant closure under
both the 40 CFR 51.308 and 309 programs, on October 7, 2015 the State
adopted an enforceable commitment into the Utah RH SIP at Chapter XX,
Section N. Utah submitted this SIP revision to EPA on October 20, 2015.
In this commitment, the State explained that it will continue to report
the historical emissions for the Carbon plant in the annual milestones
reports from 2016 through the life of the backstop trading program. In
addition, the State has committed to making revisions as necessary to
SIP Section XX.D.3.c (``Triggering the Trading Program'') and State
rule R307-150 (``Emission Inventories Program'') as well as any other
applicable provisions to implement the requirement for reporting
Carbon's historical emissions under the 309 program. The State notes it
will follow its SIP adoption process when making these SIP revisions.
The SIP will be adopted by the Governor-appointed Air Quality Board
through a rulemaking process that includes public participation. Once
approved into the SIP, the commitment will be enforceable by both EPA
and citizens under the CAA.
The State noted that EPA has historically recognized that, under
certain circumstances, issuing full approval may be appropriate for a
SIP submission that consists of, in part, an enforceable commitment.
Utah explained that its October 2015 submission satisfies EPA's
requirements for enforceable commitments because it has adopted such a
commitment for what is a small portion of its regional haze program in
relation to its regional haze obligations as a whole. In addition,
Carbon's 8,005 tpy SO2 emissions reductions is small in
comparison to the 2018 milestone of 141,849 tpy described in Table 7.
On the matter of timing, the State has committed to providing the
required subsequent SIP submittal by mid-March 2018.
E. Consultation With FLMs
Utah's SIPs do not specifically discuss how it addressed the
requirements of 40 CFR 308(i)(2) for providing the FLMs with an
opportunity for consultation at least 60 days prior to holding the
public hearing for the June 2015 RH SIP. However, we are aware that
Utah consulted with the FLMs and explain those efforts here. The State
held an initial public comment period for proposed SIP amendments from
November 1 through December 22, 2014. The State provided the
opportunity for the FLMs to review the preliminary draft SIP documents
via email approximately 68 days prior to the public hearing that was
held on a December 1, 2014. Copies of the email correspondence
documenting this effort are included in the docket.
Utah received a number of comments during the public comment period
in late 2014. After reviewing the comments and consulting with EPA,
Utah determined additional work was needed to develop a BART
alternative measure that would take credit for emission reductions from
the Carbon plant shutdown among other things. Utah held an additional
public comment period from April 1 through April 30, 2015. One of the
FLMs, the National Park Service, provided extensive public comments to
Utah during this second public comment period and Utah included
responses to these comments, along with responses to other commenters,
in the June 2015 RH SIP submittal along with other administrative
documentation.
The October 2015 Utah RH SIP was provided for public comment August
15 through September 14, 2015, and we are not aware of any prior FLM
consultation on this SIP. The FLMs did not submit comments during this
public comment period.
V. EPA's Evaluation and Proposed Approval of Utah's Regional Haze SIP
As explained in section II.A, EPA is soliciting comments on two
alternative proposals: A proposal to approve the State SIP in its
entirety, and a proposal to partially approve and partially
[[Page 2021]]
disapprove the State SIP and to issue a FIP. The co-proposals detailed
in this section and Section VI represent different conclusions
regarding Utah's NOX BART Alternative and the metrics the
State has proposed to support this alternative. As described in this
section, EPA is proposing to approve the two Utah 2015 RH SIP
revisions. Alternatively, as discussed in section VI, EPA is co-
proposing to disapprove the Utah's June 2015 and October 2015 RH SIP
revisions and promulgate a FIP.
This document is written as two separate proposals in order to
clearly present the options and solicit comment on each. EPA intends to
finalize only one of these co-proposals; however, we also acknowledge
that additional information and comments may also lead the Agency to
adopt final SIP and/or FIP regulations that differ somewhat from the
co-proposals presented here regarding the BART Alternative, BART
control technology option or emission limits, or impact other proposed
regulatory provisions.
A. Basis for Proposed Approval
For the reasons described later on, EPA proposes to approve the two
Utah 2015 RH SIP revisions. Our proposed action is based on an
evaluation of Utah's regional haze SIP submittals against the regional
haze requirements at 40 CFR 51.300-51.309 and CAA sections 169A and
169B. All general SIP requirements contained in CAA section 110, other
provisions of the CAA, and our regulations applicable to this action
were also evaluated. The purpose of this proposed action is to ensure
compliance with these requirements and to provide additional rationale
to support our conclusions.
B. Utah BART Alternative
1. Summary of Utah BART Alternative
Utah has opted to establish an alternative measure (or program) for
NOX in accordance with 40 CFR 51.308(e)(2). A description of
the Utah BART Alternative is provided in section IV.B.1. The RHR
requires that a SIP revision establishing a BART alternative include
three elements as listed later. We have evaluated the Utah BART
Alternative with respect to each of these elements.
A demonstration that the emissions trading program or
other alternative measure will achieve greater reasonable progress than
would have resulted from the installation and operation of BART at all
sources subject to BART in the State and covered by the alternative
program.\77\
---------------------------------------------------------------------------
\77\ 40 CFR 51.308(e)(2)(i).
---------------------------------------------------------------------------
A requirement that all necessary emissions reductions take
place during the period of the first long-term strategy for regional
haze.\78\
---------------------------------------------------------------------------
\78\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------
A demonstration that the emissions reductions resulting
from the alternative measure will be surplus to those reductions
resulting from measures adopted to meet requirements of the CAA as of
the baseline date of the SIP.\79\
---------------------------------------------------------------------------
\79\ 40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------
2. Demonstration of Greater Reasonable Progress for the Alternative
Program
As discussed previously in section III.E.1, pursuant to 40 CFR
51.308(e)(2)(i), Utah must demonstrate that the alternative measure
will achieve greater reasonable progress than would have resulted from
the installation and operation of BART at all sources subject to BART
in the State and covered by the alternative program. This
demonstration, primarily included in Chapter 1 of the TSD of the Utah
RH SIP,\80\ must be based on five criteria which are addressed later.
---------------------------------------------------------------------------
\80\ As presented in this proposal, while the majority of the
State's demonstration is contained in Chapter 1, EPA has identified
additional information regarding the demonstration and we include
references to the additional information.
---------------------------------------------------------------------------
a. A List of All BART-Eligible Sources Within the State
As discussed previously in section IV.A.2, Utah included a list of
BART-eligible sources and noted the following sources are all covered
by the alternative program:
PacifiCorp Hunter, Unit 1
PacifiCorp Hunter, Unit 2
PacifiCorp, Huntington, Unit 1
PacifiCorp, Huntington, Unit 2
EPA previously approved Utah's BART eligibility determinations in
our 2012 rulemaking.\81\
---------------------------------------------------------------------------
\81\ 77 FR 74357 (Dec. 14, 2012).
---------------------------------------------------------------------------
b. A List of All BART-Eligible Sources and All BART Source Categories
Covered by the Alternative Program
As discussed previously in section IV.A.3, the Utah BART
Alternative covers all the BART-eligible sources in the state, Hunter
Units 1 and 2 and Huntington Units 1 and 2, in addition to three non-
BART units, PacifiCorp's Hunter Unit 3 and Carbon Units 1 and 2. EPA
previously approved Utah's BART eligibility determinations in our 2012
rulemaking.\82\
---------------------------------------------------------------------------
\82\ 77 FR 74355, 74357 (Dec. 14, 2012).
---------------------------------------------------------------------------
c. Analysis of BART and Associated Emission Reductions
As noted in section IV.C.3, in the June 2015 Utah RH SIP, the State
compared the Utah BART Alternative to a BART Benchmark that included
the most stringent NOX BART controls, SCR plus new LNBs and
SOFA, at the four BART units. This is consistent with the streamlined
approach described in Step 1 of the BART Guidelines. The BART
Guidelines note that a comprehensive BART analysis can be avoided if a
source commits to a BART determination that consists of the most
stringent controls available.\83\
---------------------------------------------------------------------------
\83\ 40 CFR 51, appendix Y, section IV.D.1.9.
---------------------------------------------------------------------------
We propose to find that Utah has met the requirement for an
analysis of BART and associated emission reductions achievable at
Hunter and Huntington under 40 CFR 51.308(e)(2)(i)(C).
d. Analysis of Projected Emissions Reductions Achievable Through the
BART Alternative
As discussed previously in section IV.C.4, a summary of Utah's
estimates of emissions for the Utah BART Alternative and the BART
Benchmark is provided in Table 3. We propose to find that Utah has met
the requirement for an analysis of the projected emissions reductions
achievable through the alternative measure under 40 CFR
51.308(e)(2)(i)(D).
e. A Determination That the Alternative Achieves Greater Reasonable
Progress Than Would Be Achieved Through the Installation and Operation
of BART
Greater Reasonable Progress Based on 40 CFR 51.308(e)(3)'s Greater
Emission Reductions Test
EPA's evaluation of the State's demonstration based on 40 CFR
51.308(e)(3) is located in section VI.B.2.e.
Greater Reasonable Progress Based on 40 CFR 51.308(e)(2)'s Weight-of-
Evidence Test
Although Utah found that the BART Alternative demonstrates greater
reasonable progress under 40 CFR 51.308(e)(3), it also chose to conduct
a weight-of-evidence analysis under 40 CFR 51.308(e)(2) based on a BART
Alternative involving the Hunter, Huntington, and Carbon power plants
and considered the following evidence:
i. Annual Emissions Comparison for Visibility-Impairing Pollutants
The emissions of visibility-impairing pollutants from both the Utah
BART Alternative and the BART Benchmark, as estimated by Utah, are
summarized in Table 3 in section IV.C.4. Compared with the Utah BART
Benchmark, the State projects that the Utah BART Alternative will
result in 5,721 tpy more
[[Page 2022]]
NOX emissions, 8,005 tpy fewer SO2 emissions, and
573 tpy fewer PM10 emissions than the BART Benchmark. Utah
also found that the combined emissions of NOX,
SO2 and PM10 will be 2,856 tpy lower under the
BART Alternative.
We propose to concur with Utah's finding that the BART Alternative
will achieve greater SO2 and PM10 emissions
reductions and greater aggregate emissions reductions of all
pollutants. We further propose to recognize that not all pollutants
impact visibility equally and that the total emissions reductions of
all pollutants is not necessarily a direct indicator of whether the
BART Alternative or the BART Benchmark will achieve greater reasonable
progress. However, for reasons described later in subsection vii for
our evaluation of Utah's IMPROVE monitoring metric, we propose to
concur with Utah's finding that SO2 emissions reductions
should provide visibility benefits in all seasons and that sulfate is
the largest contributor to visibility impairment at the affected Class
I areas. Furthermore, we propose to find that these observations
suggest that the BART Alternative is likely to achieve greater
reasonable progress. We note that Utah has also provided CALPUFF
modeling results for the BART Benchmark and BART Alternative scenarios
to assess the relative visibility benefits of each. These modeling
results are considered here by EPA as part of the overall weight-of-
evidence analysis.
ii. Improvement in the Number of Days With Significant Visibility
Impairment
As discussed previously in section IV.C.5, Utah provided modeling
results to assess the improvement in the number of days with
significant visibility impairment--that is, the improvement in the
number of days with impacts that either cause (>1.0 dv) or contribute
(>0.5 dv) to visibility impairment.
The BART Guidelines provide that, when making a BART determination,
a State may consider the number of days or hours that a threshold was
exceeded.\84\ In developing the BART Guidelines, our example modeling
analysis of a hypothetical source examined the number of days that 1.0
dv and 0.5 dv thresholds were exceeded.\85\ In addition, we have used
these metrics, and in particular the total number of days for the
meteorological years modeled, in previous regional haze rulemakings
such as for North Dakota,\86\ Montana,\87\ and Washington.\88\
---------------------------------------------------------------------------
\84\ 40 CFR 51, appendix Y, section IV.D.5.
\85\ 70 FR 39130 (July 6, 2005).
\86\ 76 FR 58584 (Sept. 21, 2011).
\87\ 77 FR 24006 (Apr. 20, 2012).
\88\ 79 FR 33438, 33440-33441 (June 11, 2014).
---------------------------------------------------------------------------
This metric is useful in assessing the frequency and duration of
significant visibility impacts from a source or small group of sources.
Therefore, for this reason and because these metrics are supported by
our regulations and past practice, we propose to find the State's use
of these metrics is appropriate. Moreover, we propose to find the
difference in the total number of days impacted--18 fewer days greater
than the causation threshold of 1.0 dv (775 days for the BART
Alternative vs. 793 days for the BART Benchmark), and 175 fewer days
greater than the contribution 0.5 dv threshold (1,323 days for the BART
Alternative vs. 1,498 days for the BART Benchmark)--is an indication
that the BART Alternative achieves greater reasonable progress.
iii. 98th Percentile Impact (dv)
As discussed previously in section IV.C.5, Utah explained that the
only metric it evaluated that showed greater improvement for the BART
Benchmark in comparison to the BART Alternative was the 98th percentile
metric (when averaged across all Class I areas and meteorological years
modeled). Utah's comparison of the modeled visibility impacts on the
98th percentile day (8th highest impacted day in a given meteorological
year) for the most impacted year shows that the BART Benchmark would
result in greater visibility improvement at five of the nine Class I
areas, and is slightly better on average across all nine Class I areas
(0.11 dv difference). At the most impacted Class I areas, Canyonlands
and Capitol Reef, Utah found that the 98th percentile metric indicates
the BART Benchmark has 0.76 dv and 0.57 dv, respectively, more
improvement than the BART Alternative. At other Class I areas, Utah
found that the 98th percentile metric indicates that the BART
Alternative provides greater visibility improvement (for example, 0.44
dv at Flat Tops).
The 98th percentile visibility impact is a key metric recommended
by the BART Guidelines \89\ when selecting BART controls. In addition,
this is one of the primary metrics that EPA has relied on in evaluating
prior regional haze actions that have included BART alternatives.\90\
In the BART Guidelines, EPA described this metric as an appropriate
measure in determining the degree of visibility improvement expected
from controls.\91\ Therefore, we propose to find that it is an
appropriate metric for assessing the relative benefits of the Utah BART
Alternative here.
---------------------------------------------------------------------------
\89\ 40 CFR 51, appendix Y, section IV.D.5.
\90\ See, e.g., 78 FR 79344 (Dec. 30, 2012)(proposed rule, FIP
for Tesoro Refining and Intalco Refinery BART Alternatives); 79 FR
33438 (June 11, 2014)(final rule, FIP for Tesoro Refining and
Intalco Refinery BART Alternatives); 79 FR 56322, 56328 (Sept. 19,
2014)(proposed approval of Arizona Apache BART Alternative); 80 FR
19220 (April 10, 2015)(final approval of Arizona Apache BART
Alternative); 77 FR 11827, 11837 (Feb. 28, 2012)(proposed approval
of Maryland BART Alternative); 77 FR 39938, 39940-1 (July 6,
2012)(final approval of Maryland BART Alternative).
\91\ 70 FR at 39129.
---------------------------------------------------------------------------
We note that when calculating visibility improvements for
individual Class I areas, Utah mixed the impacts from different
meteorological years between modeling scenarios (baseline, BART
benchmark, and BART Alternative). This may introduce some error as the
visibility improvements could be driven by year-to-year variability in
meteorological conditions, as opposed to the differences in emission
reductions between the BART Alternative and BART Benchmark. For this
reason, in addition to considering the State's numbers, EPA also
calculated the visibility improvements for each modeling scenario using
consistent meteorological years.\92\ Using this method, whether the
BART Alternative resulted in lower 98th percentile impacts depended on
both the particular Class I area and meteorological year modeled. In
some years and some Class I areas, particularly some of the most
impacted Class I areas, the BART Benchmark shows better visibility
improvement than the BART Alternative. Notably, the BART Benchmark
shows 0.93 dv greater improvement for Canyonlands in 2002 and 0.75 dv
greater improvement for Capitol Reef in 2001.\93\ By contrast, the BART
Alternative shows 0.90 dv greater improvement for Arches in 2003 and
0.43 dv greater improvement for Flat Tops in 2002.\94\ On the whole,
when using this method, the BART Benchmark is better on average across
all years and nine Class I areas (0.14 dv difference). See Table 12. We
propose to find, consistent with the State's evaluation, that this
metric favors the BART Benchmark.
---------------------------------------------------------------------------
\92\ See EPA Calculation of 98th Percentile Improvement for Utah
Bart Alternative spreadsheet (in docket).
\93\ Id.
\94\ Id.
[[Page 2023]]
Table 12--Summary of EPA Comparison of Utah CALPUFF 98th Percentile
Modeling Results Based on Consistent Meteorological Years 95
------------------------------------------------------------------------
Average
visibility
improvement of
Class I Area BART benchmark
over BART
alternative
(delta dv)\1\
------------------------------------------------------------------------
Arches............................................... -0.21
Black Canyon of the Gunnison......................... 0.06
Bryce Canyon......................................... 0.04
Canyonlands.......................................... 0.78
Capitol Reef......................................... 0.59
Flat Tops............................................ -0.15
Grand Canyon......................................... 0.06
Mesa Verde........................................... 0.12
Zion................................................. 0.02
Class I Area Average................................. 0.14
------------------------------------------------------------------------
\1\ A negative value indicates the modeling results favor the BART
Alternative. Results are based on the three-year average of results
for 2001, 2002 and 2003.
iv. Annual Average Impact (dv)
As discussed previously in section IV.C.5, Utah's modeling shows
that the average annual dv impact at all Class I areas is better under
the Utah BART Alternative at five of the nine Class I areas, and is
better on average across all the Class I areas. The average impact was
calculated by averaging all daily modeling results for each year and
then calculating a 3-year average from the annual average. Utah's
information shows that the BART Alternative is better than the BART
Benchmark by 0.009 dv on average across all nine Class I areas. While
EPA has not considered this metric in the past,\96\ since the State
includes it, we consider it here. Furthermore, the BART Guidelines
state that, ``in determining what, if any, emission controls should be
required, the State will have the opportunity to consider the
frequency, duration, and intensity of a source's predicted effect on
visibility.'' \97\ The annual average does provide an indication of the
modeled visibility impacts for the entire year while the 98th
percentile modeled results speak to a particular day (the 8th highest
impacted day). Accordingly, and while we have typically relied
primarily on the 98th percentile impacts in evaluating BART controls in
other actions, we propose to find that the annual average impact
provides additional useful information in considering Utah's weight of
evidence. However, given that the difference in this metric is small
(0.009 dv), we propose to find that it only marginally supports a
conclusion that the BART Alternative achieves greater reasonable
progress.
---------------------------------------------------------------------------
\95\ Id.
\96\ EPA final actions on BART alternatives that evaluated
CALPUFF modeling analysis, which did not include consideration of
annual average dv impacts include: 80 FR 19220 (April 10,
2015)(Region 9, Apache); 79 FR 33438 (June 11, 2014)(Region 10,
Tesoro Refining and Alcoa Intalco Operations); 77 FR 39938 (July 6,
2012)(Region 3, Maryland HAA).
\97\ 70 FR 39121 (July 5, 2005).
---------------------------------------------------------------------------
v. 90th Percentile Impact (dv)
As discussed previously in section IV.C.5, Utah's comparison of the
modeled visibility impacts at the 90th percentile (the 110th highest
day across three years) dv impact shows that the Utah BART Alternative
is better at seven of the nine Class I areas and is slightly better
averaged both across three years and across nine Class I areas (0.006
dv difference). We note that the use of the 90th percentile impacts to
evaluate alternatives has not been EPA's practice for source-specific
BART determinations; however, as discussed previously for the average
dv impact metric, the BART Guidelines allow states to consider other
visibility metrics in addition to the 98th percentile. Yet, because of
the small difference between the two scenarios (0.006 dv), we propose
to find that it only marginally supports a conclusion that the BART
Alternative achieves greater reasonable progress.
vi. Timing for the Emissions Reductions
As discussed previously in section IV.C.5, Utah noted that
reductions under the Utah BART Alternative will occur earlier than the
BART Benchmark. The reductions under the Utah BART Alternative are
required under the State SIP by August 2015, as noted in Table 5,
providing an early and on-going visibility benefit as compared to BART.
Also notable is that combustion control upgrades at the Hunter and
Huntington facilities have been achieving significant NOX
reductions since the time of their installation between 2006 and 2014,
depending on the unit. If, as proposed in section VI.C, BART for the
four units is LNB/SOFA plus SCR, BART likely would be fully implemented
sometime between 2019 and 2021.
Therefore, we note that the reductions from the BART Alternative
will occur before the BART Benchmark.
vii. IMPROVE Monitoring Data
Utah's SIP presents sulfate and nitrate monitoring data at the
Canyonlands IMPROVE monitor that show that ``sulfates are the dominant
visibility impairing pollutant'' \98\ and that sulfate levels have
decreased,\99\ and references similar results at other Class I areas in
the TSD.\100\ Utah also presents data on trends in emissions from EGUs
showing substantial reductions in emissions of both SO2 and
NOX.\101\ Based on these data, Utah indicates it ``has
confidence that the SO2 reductions will achieve meaningful
visibility improvement,'' under the Utah BART Alternative, while ``the
visibility improvement during the winter months due to NOX
reductions is much more uncertain.'' \102\ Utah makes this point even
though nitrate concentrations are highest in the winter, explaining
that while there has been a reduction in NOX, the ammonium
nitrate values do not show similar improvement in the winter
months.\103\ Utah offers several possible explanations for the results,
but does not provide any definitive conclusions.\104\
---------------------------------------------------------------------------
\98\ Utah Regional Haze State Implementation Plan, Technical
Support Document, Ch. 1, p. 12 (2015).
\99\ Id. at p. 15.
\100\ Id. at p.12.
\101\ Id. at p. 14.
\102\ Id. at p. 13.
\103\ Id.
\104\ Id. at pp. 16-19.
---------------------------------------------------------------------------
Utah also presents data on the seasonality of park visitation and
monitoring data for nitrate and sulfates. The data show that the
highest measured nitrate concentrations occur in winter during the
period of lowest park visitation, and that sulfates affect visibility
throughout the year and are the dominant visibility impairing pollutant
from anthropogenic sources during the high visitation period of March
through November. Utah concludes that it has greater confidence that
reductions in SO2 will be reflected in improved visibility
for visitors to the Class I areas, while reductions in NOX
will have a more uncertain benefit for visitors to Class I areas.
We invite comment on the information and conclusions provided by
Utah as summarized previously.
We propose to concur with one of the State's findings. We propose
to find that visibility benefits associated with NOX
reductions are much more likely to occur in the winter months because
this is when aerosol thermodynamics favors nitrate formation.\105\ By
contrast, SO2 emissions reductions should provide
[[Page 2024]]
visibility benefits in all seasons.\106\ We also propose to find that,
as concluded by the GCVTC, and supported by the IMPROVE monitoring data
presented by Utah, anthropogenic visibility impairment on the Colorado
Plateau is dominated by sulfates.107 108 Therefore, we
propose to concur with Utah's statement that sulfate is the largest
contributor to visibility impairment at the affected Class I areas.
---------------------------------------------------------------------------
\105\ Fountoukis, C. & Nenes, A. ISORROPIA II: A Computationally
Efficient Aerosol Thermodynamic Equilibrium Model for K+,
Ca2+, Mg2+,
NH4+, Na+,
SO42-, NO3-, Cl-,
H2O Aerosols, 7 Atmos. Chem. Phys., 4639-4659 (2007).
\106\ Seinfeld, John H., Urban Air Pollution: State of the
Science, 243 Science Magazine, No. 4892, 745, 745-752 (1989).
\107\ While natural sources of haze from wildfires or windblown
dust can be the largest contributor on some of the 20% haziest days,
the RHR defines ``impairment'' as anthropogenic impairment, and
sulfate formed from anthropogenic SO2 emissions is the
dominant contributor to anthropogenic visibility impairment on the
haziest days.
\108\ The Grand Canyon Visibility Transport Commission
Recommendations for Improving Western Vistas, June 10, 1996, p. 32.
Available at http://www.wrapair.org/WRAP/reports/GCVTCFinal.PDF and
included in the docket.
---------------------------------------------------------------------------
We propose to disagree with the State's findings related to park
visitation. While the BART Guidelines do mention visitation as
something that can inform a control decision,\109\ EPA is proposing to
place little weight on the State's correlation of emissions reductions
and park visitation because nothing in the CAA suggests that visitors
during busy time periods are entitled to experience better visibility
than visitors during off-peak periods. On the contrary, in the Regional
Haze provisions of the CAA, Congress declared a national goal of
remedying all manmade visibility impairment in all class I areas, which
includes both heavily-visited national parks and seldom-visited
wilderness areas. We invite comment on our evaluation and the
information and conclusions provided by Utah as summarized previously.
---------------------------------------------------------------------------
\109\ 70 FR 39104, 39130 (July 6, 2005) (``Other ways that
visibility improvement may be assessed to inform the control
decisions would be to examine distributions of the daily impacts,
determine if the time of year is important (e.g. high impacts are
occurring during tourist season), consideration of the cost-
effectiveness of visibility improvements (i.e. the cost per change
in deciview), using the measures of deciview improvement identified
by the State, or simply compare the worst case days for the pre- and
post-control runs. States may develop other methods as well.'').
---------------------------------------------------------------------------
viii. Energy and Non-Air Quality Benefits
As discussed previously in section IV.C.5, the State noted that the
Utah BART Alternative would avoid an annual energy penalty of
approximately $2 million due to operating four SCR units at the Hunter
and Huntington plants and presented additional non-air quality benefits
associated with the closure of the Carbon plant such as waste reduction
and decreased water usage. Because such benefits do not have direct
bearing on whether the BART Alternative achieves greater reasonable
progress, it is not material to our action whether we agree or disagree
with Utah's assessment that they reduce energy and non-air quality
impacts.
ix. Cost
As discussed previously in section IV.C.5, the State noted that the
Utah BART Alternative would achieve greater reasonable progress at
lower cost to PacifiCorp than the BART Benchmark. Utah also noted that
cost is one of the factors listed in CAA 169A(g)(2) that should be
considered when determining BART. While we propose to find that the
described cost difference does not have a direct bearing on whether the
BART Alternative achieves greater reasonable progress, it is not
material to our action whether we agree or disagree with Utah's
conclusion that the BART Alternative would have a lower cost impact to
PacifiCorp than the BART Benchmark (i.e., costs provided by PacifiCorp
in its BART analyses of August 5, 2014, SIP TSD Chapter 2). However, we
do agree.
f. Evaluation of the Weight of Evidence
In accordance with our regulations governing BART alternatives, we
support the use of a weight-of evidence determination as an alternative
to the methodology set forth in section 51.308(e)(3).\110\ In
evaluating Utah's weight-of-evidence demonstration, we have evaluated
all nine elements of Utah's analysis, and as discussed later, rely
primarily on the following four elements in proposing to approve the
BART Alternative: Annual emissions comparison for two pollutants;
improvement in the number of days with significant visibility
impairment; IMPROVE monitoring data regarding sulfates; and the early
timing for installation of controls. Additional elements that either
marginally support or do not support our proposed approval of Utah's
determination are also discussed later.
---------------------------------------------------------------------------
\110\ 71 FR 60622 (Oct. 13, 2006).
---------------------------------------------------------------------------
Regarding the emissions reduction comparison, the Utah BART
Alternative will result in 8,005 tpy fewer SO2 emissions
compared to the BART Benchmark. In addition, the combined emissions of
NOX, SO2 and PM10 will be 2,856 tpy
lower under the BART Alternative.
Regarding the improvement in the number of days with significant
visibility impairment, modeling submitted by Utah shows that the Utah
BART Alternative will result in improved visibility at all affected
Class I areas compared with baseline conditions. The units at issue
will have impacts of 1.0 dv or more at the affected Class I areas on 48
fewer days under the Utah BART Alternative as compared to BART. When
considering impacts of 0.5 dv or more, the units at issue will impact
the affected Class I areas on 154 fewer days under the BART Alternative
as compared to BART.
Regarding the IMPROVE visibility monitoring data, we propose to
agree with the State's finding that SO2 emissions reductions
provide visibility benefits throughout the year. We also propose to
concur with Utah's statement that sulfate is the largest contributor to
visibility impairment at the affected Class I areas.
Regarding the timing of emissions reductions, these SO2
emissions reductions were achieved in August 2015, the date in the June
2015 Utah RH SIP requiring the closure of the Carbon plant. Combustion
controls at the four BART units in addition to Hunter Unit 3 were
installed between 2006 and 2014. BART likely would otherwise have been
implemented sometime between 2019 and 2021. So the Utah BART
Alternative provides early and on-going visibility benefits as compared
to BART.
Regarding other metrics that only marginally support or do not
support our proposed approval of Utah's BART Alternative, we propose to
find that average annual dv impact and the 90th percentile impact are
the two metrics that marginally support a conclusion that the BART
Alternative achieves greater reasonable progress.
Regarding the 98th percentile visibility impact, we propose to find
this metric does not support our proposed approval of Utah's BART
Alternative. While the 98th percentile visibility impact is a key
metric that EPA has primarily focused on in prior actions, we propose
to conclude that by itself it is not a dispositive metric in weighing a
BART Alternative. Nonetheless, as discussed in section VI, we have
given considerable weight to this metric in previous actions where we
have evaluated BART alternatives as it captures a source's likely
greatest visibility impacts at a Class I area; as such, it is a useful
comparison point for determining whether one emission control scenario
will have a greater impact on visibility improvement than another. In
those actions, the 98th percentile visibility impact favored the BART
alternative and therefore there was less need to introduce and consider
additional evidence to determine
[[Page 2025]]
whether an alternative would provide greater reasonable progress. In
the case of the Utah BART Alternative, where the 98th percentile does
not favor the alternative, Utah has introduced additional evidence that
we considered in order to evaluate whether the BART Alternative, on
balance, achieves greater reasonable progress.
Regarding the 90th percentile visibility impact, we propose to find
that consideration of this metric is appropriate in assessing the
weight of evidence associated with a BART alternative. Visibility at a
Class I area changes from day to day, and each emission control
scenario would result in visibility improvements at the affected Class
I areas that would differ from one day to another. The metrics related
to the number of days with impacts greater than 0.5 dv and 1.0 dv are
examples of the type of additional information that allows for
consideration of the frequency and duration of visibility impacts.
Similarly, the use of the 90th percentile impact metric allows for the
comparison of BART and a BART alternative at a different point in the
range of impacts. This can be useful, given the varying impacts of
different pollutants under different meteorological conditions. The
information provided by Utah for the 90th percentile shows that the
BART Alternative is better at seven of the nine Class I areas for this
metric, by amounts ranging from 0.019 to 0.140 dv, and is better when
taking into account the impacts averaged both across three years and
across nine Class I areas, but only by 0.006 dv. These values
marginally support our proposed approval of Utah's BART Alternative as
better than BART. We invite comment on this proposed assessment of how
the 90th percentile metric should be considered in the weight of
evidence determination. We also invite interested parties to submit
additional information on how the impacts of the BART Alternative under
various conditions compare to the impacts of the presumed BART
scenario, because while the 90th percentile impact provides additional
insight, it is not uniquely informative.
Regarding the energy and non-air quality impacts, as well as cost,
we propose to find these metrics do not have direct bearing on whether
the Utah BART Alternative achieves greater reasonable progress than the
BART Benchmark; and therefore, we have not taken them into
consideration.
Consistent with EPA's regulations governing BART alternatives,\111\
in evaluating the weight-of-evidence demonstration, we have evaluated
all of the information and data submitted by Utah, while recognizing
the relative strengths and weaknesses of that information to arrive at
our proposed decision. Based on the weight-of-evidence presented, we
propose to approve Utah's determination that the Utah BART Alternative
would achieve greater reasonable progress than BART under 40 CFR
51.308(e)(2)(i)(I).
---------------------------------------------------------------------------
\111\ 71 FR 60622 (Oct. 13, 2006).
---------------------------------------------------------------------------
g. Requirement That Emission Reductions Take Place During Period of
First Long-Term Strategy
As discussed previously in section IV.C.6, pursuant to 40 CFR
51.308(e)(2)(iii), the State must ensure that all necessary emission
reductions take place during the period of the first long-term strategy
for regional haze, i.e., by December 31, 2018. The RHR further provides
that, to meet this requirement, the State must provide a detailed
description of the alternative measure, including schedules for
implementation, the emission reductions required by the program, all
necessary administrative and technical procedures for implementing the
program, rules for accounting and monitoring emissions, and procedures
for enforcement.\112\
---------------------------------------------------------------------------
\112\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------
As noted previously, the Utah SIP revision incorporates the
revisions to R307-110-17, Section IX, Control Measures for Area and
Point Sources, Part H, Emissions Limits, which includes provisions for
implementing the Utah BART Alternative. In addition to the emission
limitations for NOX and PM10, and the requirement
for shutdown of the Carbon plant listed in Table 2, the SIP includes
compliance dates, operation and maintenance requirements, and
monitoring, recordkeeping, and reporting requirements. We propose to
find that these provisions meet the requirements of 40 CFR
51.308(e)(2)(iii).
h. Demonstration That Emission Reductions From Alternative Program Will
Be Surplus
i. June 2015 Utah RH SIP
As discussed previously in section IV.C.7, pursuant to 40 CFR
51.308(e)(2)(iv), the SIP must demonstrate that the emissions
reductions resulting from the alternative measure will be surplus to
those reductions resulting from measures adopted to meet requirements
of the CAA as of the baseline date of the SIP. The baseline date for
regional haze SIPs is 2002.\113\ As discussed in section IV.C.7, all of
the emission reductions required by the Utah BART Alternative result
from measures applicable to Hunter, Huntington and Carbon that occur
after 2002.
---------------------------------------------------------------------------
\113\ See Memorandum from Lydia Wegman and Peter Tsirigotis,
2002 Base Year Emission Inventory SIP Planning: 8-hr Ozone,
PM2.5, and Regional Haze Programs, November 18, 2002.
http://www3.epa.gov/ttnchie1/eidocs/2002baseinven_102502new.pdf.
---------------------------------------------------------------------------
Furthermore, the State's SIP explains that the WRAP modeling that
was done to support the Utah RH SIP included regional SO2
emissions based on the 2018 SO2 milestone and also included
NOX and PM10 emissions from the Carbon plant.
Thus, WRAP did not rely on emission reductions from the Carbon plant in
establishing the 2018 SO2 milestone.
The State's SIP also includes SO2 trend data that
further demonstrate emission reductions from the Carbon plant do not
appear to be needed for meeting the 2018 milestone of 141,849 tpy.
Actual emissions in the three-state region are calculated each year and
compared to the milestones. As can be seen in Table 7, SO2
emissions reported for 2011 are below the 2018 milestone and the most
recent milestone report for 2013 demonstrates that SO2
emissions are currently 26 percent lower than the 2018 milestone.
Additionally, the Carbon plant was fully operational in the years 2011-
2013 when the emissions from the three-state region were below the 2018
milestone for those years. Therefore, the SO2 emission
reductions from the closure of the Carbon plant appear to be surplus to
what is needed to meet the 2018 milestone established in Utah's RH SIP.
ii. October 2015 Utah RH SIP
As discussed previously in section IV.D, Utah submitted enforceable
commitments in its October 20, 2015 SIP to address potential concerns
that the State would be double counting SO2 emissions
reductions for the Carbon plant closure under both the 40 CFR 51.308
and 309 programs.\114\
---------------------------------------------------------------------------
\114\ Regional Haze Section XX, N. (1).
---------------------------------------------------------------------------
EPA has historically recognized that under certain circumstances,
it is appropriate to approve a SIP submission that consists, in part,
of an enforceable commitment. Once EPA determines that circumstances
warrant consideration of an enforceable commitment to meet section
110(a)(2)(A) of the Act (and other applicable sections as relevant),
EPA applies three factors to determine whether to approve the
enforceable commitment: (1) Whether the commitment addresses a limited
portion
[[Page 2026]]
of the statutorily-required program; (2) whether the state is capable
of fulfilling its commitment; and (3) whether the commitment is for a
reasonable and appropriate period of time. Once approved in a SIP, the
commitments are enforceable by both EPA and citizens under the Act.
First, Utah's revisions address a limited portion of the
statutorily-required program. The Air Quality Board adopted revisions
to SIP Section XX, Regional Haze, and added a new subsection N,
``Enforceable Commitments for the Utah Regional Haze SIP'' that
resolves specific identified issues. In this provision of the SIP,
``[t]he State commits to resolving this double counting issue by
revising the Utah 309 plan to specifically state that the 8,005 tons of
SO2 emissions from the Carbon units will be added into the
annual milestone reports from 2016 through the life of the backstop
trading program, thereby removing any credit for that emission
reduction in meeting the levels specified in the Utah 309 plan.'' \115\
Reporting Carbon's emissions in this manner is reasonable and ensures
that these emissions reductions are only credited under the BART
Alternative.
---------------------------------------------------------------------------
\115\ Regional Haze SIP Section XX, N. (1).
---------------------------------------------------------------------------
The SIP indicates the Board is capable of fulfilling these
commitments by explaining that ``[a]ll required amendments to this SIP
will be done through the State's SIP adoption process'' \116\ and that
``[t]he SIP is adopted by the Governor-appointed Air Quality Board
through a rulemaking process that includes public comment periods and
an opportunity for a public hearing.'' \117\
---------------------------------------------------------------------------
\116\ Regional Haze SIP Section XX, N. (4).
\117\ Regional Haze SIP Section XX, N. (4).
---------------------------------------------------------------------------
The SIP commits to resolve the identified issues (``SIP Section
XX.D.3.c and [the State's rule] R307-150 will be revised . . .''
\118\), and any other related issues, within reasonable amount of time
(``Utah will work with EPA and take appropriate action to resolve any
completeness or approvability issues that arise regarding the proposed
SIP revision by March 2018'' \119\). This will allow sufficient time
for EPA to act on the submittal before the end of the milestone
commitment.
---------------------------------------------------------------------------
\118\ Regional Haze SIP Section XX, N. (3).
\119\ Regional Haze SIP Section XX, N. (6), (3).
---------------------------------------------------------------------------
We also propose to concur that Carbon's 8,005 tpy of SO2
emissions reductions is a limited portion of the overall requirements
of the 309 program and particularly in comparison to the 2018
SO2 milestone of 141,849 tpy described in Table 7.\120\
---------------------------------------------------------------------------
\120\ Regional Haze SIP Section XX, N. (2).
---------------------------------------------------------------------------
Based on these considerations, we propose to approve the
enforceable commitment SIP.
Therefore, based on the information presented previously from the
State's SIP and enforceable commitment SIP, we propose to concur that
the reductions from Carbon are surplus and can be considered as part of
an alternative strategy under 40 CFR 51.308(e)(2)(iv).
C. PM10 BART Determinations
As discussed previously in section IV.B.2, Utah determined that the
PM10 BART emission limit for Hunter Units 1 and 2 and
Huntington Units 1 and 2 was 0.015 lb/MMBtu based on a three-run test
average. Utah noted that because the most stringent technology is in
place at these units and that the PM10 emission limits have
been made enforceable in the SIP, no further analysis was required.
EPA has reviewed Utah's PM10 BART streamlined five-
factor analysis and PM10 BART determinations for Hunter
Units 1 and 2 and Huntington Units 1 and 2 and proposes to find that
these determinations meet the requirements of 40 CFR 51.309(d)(4)(vii).
The fabric filter baghouses installed at these BART units are
considered the most stringent technology available. The emission limit
of 0.015 lb/MMBtu at these units represents the most stringent emission
limit for PM10. Utah's use of a streamlined approach to the
five-factor analysis is reasonable as the BART Guidelines provide that
a comprehensive BART analysis can be avoided if a source commits to a
BART determination that consists of the most stringent controls
available.\121\
---------------------------------------------------------------------------
\121\ 40 CFR 51, appendix Y, section IV.D.1.9.
---------------------------------------------------------------------------
Utah's regulatory text provides, ``[e]missions of particulate (PM)
shall not exceed 0.015 lb/MMBtu heat input from each boiler based on a
3-run test average.'' It further states that ``[s]tack testing for the
emission limitation shall be performed each year on each boiler.''
\122\ We note that BART limits must apply at all times. See CAA section
302(k), 40 CFR part 51, appendix Y, section V. Furthermore, EPA's
credible evidence rule requires that a state's plan must not preclude
the use of any credible evidence or information, which can include
evidence and information other than the test method specified in the
plan, that would indicate whether a source was in compliance with
applicable requirements.\123\
---------------------------------------------------------------------------
\122\ June 2015 Utah RH SIP, Sections IX.H.22.a.i.A-B,
IX.H.22.b.i.A-B.
\123\ 40 CFR 51.212(c).
---------------------------------------------------------------------------
Consistent with these requirements, we propose to interpret Utah's
regulatory text as imposing a PM limit of 0.015 lb/MMBtu that applies
at all times and does not preclude the use, including the exclusive
use, of any credible evidence or information, relevant to whether a
source is in compliance with the limit.
D. Monitoring, Recordkeeping, and Reporting
EPA has reviewed Utah's monitoring, recordkeeping and reporting
measures in its June 4, 2015 SIP Section IX, Part H for the BART
Alternative and the PM10 BART determinations and proposes to
approve these measures as meeting the requirements of section 110(a)(2)
of the CAA and 40 CFR 51, subpart K, Source Surveillance, with the
exception of reporting requirements for violations of PM10
emissions limitations. For PM10 reporting, we are proposing
to conditionally approve this element in accordance with CAA section
110(k)(4) based on Utah's commitment to submit specific measures to
address the reporting requirement.\124\ Utah's letter commits to adopt
and submit rule language that would require sources to report any
deviation from the requirements of the RH SIP provisions, which would
include the PM10 emission limitations. The specific language
is detailed in Utah's commitment letter.
---------------------------------------------------------------------------
\124\ Letter from Department of Environmental Quality, State of
Utah to EPA, DAQP-120-15 (Dec. 10, 2015).
---------------------------------------------------------------------------
Otherwise, the SIP includes adequate measures that pertain to
operation of Hunter and Huntington and the closure of Carbon. EPA
previously approved state rule provisions that Utah has also cross
referenced in these new regional haze measures, including terms,
conditions and definitions in R307-101-1, R307-101-2 and R307-170-4 as
well as other continuous emission monitoring system (CEMS) requirements
referenced in R307-107. These measures are consistent with similar
monitoring, recordkeeping, and reporting requirements that EPA has
approved in other states or that we have adopted in federal plans,\125\
and in particular contain the requirements that were missing from
Utah's prior regional haze submittals.\126\ As described previously in
section IV.A.3, Utah has provided the emission limitations, work
practice standards, monitoring, recordkeeping, and reporting
[[Page 2027]]
requirements for all the units that are part of Utah's BART Alternative
for the Hunter, Huntington, and Carbon plants.
---------------------------------------------------------------------------
\125\ 77 FR 57864; 79 FR 5032.
\126\ 77 FR 74365-74366 (Dec. 14, 2012).
---------------------------------------------------------------------------
If we finalize our proposed approval, the regulatory text contained
in our final rule for 40 CFR part 52 subpart TT will be consistent with
the relevant provisions of Utah's regional haze submittals for making
the emission limits and other requirements enforceable. If EPA
finalizes the conditional approval of Utah's PM10 reporting
provision, the State has one year from the date of EPA's final action
on the June 4, 2015 SIP to submit the necessary SIP revisions. If the
State fails to meet its commitment within the one-year period, the
approval is treated as a disapproval. EPA proposes to find that the
necessary SIP revisions meet EPA's criteria for conditional approvals
\127\ as the revisions appear to involve a limited amount of technical
work, are anticipated to be non-controversial, and can reasonably be
accomplished within the length of time for the State's adoption
process.
---------------------------------------------------------------------------
\127\ See Memorandum from John Calcagni to EPA Regional
Directors. ``Processing of State Implementation Plan (SIP)
Submittals'' (July 1992), available at http://www3.epa.gov/ttn/oarpg/t1/memoranda/siproc.pdf.
---------------------------------------------------------------------------
E. Consultation with FLMs
As discussed previously in section IV.G, Utah conducted FLM
consultation during late 2014, providing over 60 days prior to the
December 1, 2014 public hearing. Subsequently, the National Park
Service provided extensive comments in response to a second public
comment period in April 2015. Based on these considerations, we propose
to find that Utah has met the requirements of 40 CFR 308(i)(2).
VI. EPA's Evaluation and Proposed Partial Approval and Partial
Disapproval of Utah's Regional Haze SIP
In this section, we present the second of two alternative proposed
actions on which EPA is soliciting comment. As explained previously in
sections II.A and V, EPA is soliciting comments on two alternative
proposals: a proposal to approve the State SIP in its entirety, and a
proposal to partially approve and partially disapprove the State SIP
and to issue a FIP. The co-proposals detailed in this section and
Section V represent different conclusions regarding Utah's
NOX BART Alternative and the metrics the State has proposed
to support this alternative.
As described in this section, EPA is proposing to partially approve
and partially disapprove Utah's June 2015 and October 2015 RH SIP
revisions and propose a FIP. Alternatively, as discussed in section V,
EPA is co-proposing in the alternative to approve Utah's June 2015 and
October 2015 RH SIP revisions.
This document is written as two separate proposals in order to
clearly present the options and solicit comment on each. EPA intends to
finalize only one of these co-proposals; however, we also acknowledge
that additional information and comments may also lead the Agency to
adopt final SIP and/or FIP regulations that differ somewhat from the
co-proposals presented here regarding the BART Alternative, BART
control technology option or emission limits, or impact other proposed
regulatory provisions.
A. Basis for Proposed Partial Disapproval and Partial Approval
For the reasons described later, EPA proposes to partially approve
and partially disapprove the two Utah 2015 RH SIP revisions. Our
proposed action is based on an evaluation of Utah's regional haze SIP
submittals against the regional haze requirements at 40 CFR 51.300-
51.309 and CAA sections 169A and 169B, as well as the supplemental
information EPA developed, such as EPA's calculations of the visibility
improvements for each modeling scenario using consistent meteorological
years in evaluating the 98th percentile modeling and referencing the
topographical maps in evaluating whether distribution of emissions
would be substantially different under the Utah BART Alternative. All
general SIP requirements contained in CAA section 110, other provisions
of the CAA, and our regulations applicable to this action were also
evaluated. The purpose of this action is to ensure compliance with
these requirements. As discussed in section V, EPA is also co-proposing
to approve the Utah's June 2015 and October 2015 RH SIP revisions.
B. Utah BART Alternative
1. Summary of Utah BART Alternative
Utah has opted to establish an alternative measure (or program) for
NOX in accordance with 40 CFR 51.308(e)(2). A description of
the Utah BART Alternative is provided in section IV.C. The RHR requires
that a SIP revision establishing a BART alternative include three
elements as listed later. We have evaluated the Utah BART Alternative
with respect to each of these elements.
A demonstration that the emissions trading program or
other alternative measure will achieve greater reasonable progress than
would have resulted from the installation and operation of BART at all
sources subject to BART in the State and covered by the alternative
program.\128\
---------------------------------------------------------------------------
\128\ 40 CFR 51.308(e)(2)(i).
---------------------------------------------------------------------------
A requirement that all necessary emissions reductions take
place during the period of the first long-term strategy for regional
haze.\129\
---------------------------------------------------------------------------
\129\ 40 CFR 51.308(e)(2)(iii).
---------------------------------------------------------------------------
A demonstration that the emissions reductions resulting
from the alternative measure will be surplus to those reductions
resulting from measures adopted to meet requirements of the CAA as of
the baseline date of the SIP.\130\
---------------------------------------------------------------------------
\130\ 40 CFR 51.308(e)(2)(iv).
---------------------------------------------------------------------------
2. Demonstration of Greater Reasonable Progress for Alternative Program
As discussed previously in section III.E.1, pursuant to 40 CFR
51.308(e)(2)(i), Utah must demonstrate that the alternative measure
will achieve greater reasonable progress than would have resulted from
the installation and operation of BART at all sources subject to BART
in the State and covered by the alternative program. This
demonstration, primarily included in Chapter 1 of the TSD of the Utah
RH SIP,\131\ must be based on five criteria presented below.
---------------------------------------------------------------------------
\131\ As presented in this proposal, while the majority of the
State's demonstration is contained in Chapter 1, EPA has identified
additional information regarding the demonstration and we include
references to the additional information.
---------------------------------------------------------------------------
a. A List of All BART-Eligible Sources Within the State
As discussed previously in section IV.C.1, Utah included a list of
BART-eligible sources and noted the following sources are all covered
by the alternative program:
PacifiCorp Hunter, Unit 1,
PacifiCorp Hunter, Unit 2,
PacifiCorp, Huntington, Unit 1, and
PacifiCorp, Huntington, Unit 2.
EPA approved Utah's BART eligibility determinations in our 2012
rulemaking.\132\
---------------------------------------------------------------------------
\132\ 77 FR 74357 (Dec. 14, 2012).
---------------------------------------------------------------------------
b. A List of All BART-Eligible Sources and All BART Source Categories
Covered by the Alternative Program
As discussed previously in section IV.A.3, the Utah BART
Alternative covers all the BART-eligible sources in the state, Hunter
Units 1 and 2 and Huntington Units 1 and 2, in addition to three non-
BART units, PacifiCorp's Hunter Unit 3 and Carbon Units 1 and 2. EPA
previously approved Utah's
[[Page 2028]]
BART eligibility determinations in our 2012 rulemaking.\133\
---------------------------------------------------------------------------
\133\ 77 FR 74357 (Dec. 14, 2012).
---------------------------------------------------------------------------
c. Analysis of BART and Associated Emission Reductions Achievable
As noted previously in section IV.C.3, in the June 2015 Utah RH
SIP, Utah compared the Utah BART Alternative to a BART Benchmark which
included the most stringent NOX BART controls, SCR plus new
LNBs and SOFA, at the four BART units. This is consistent with the
streamlined approach described in Step 1 of the BART Guidelines. The
BART Guidelines note that a comprehensive BART analysis can be avoided
if a source commits to a BART determination that consists of the most
stringent controls available.\134\
---------------------------------------------------------------------------
\134\ 40 CFR 51, appendix Y, section IV.D.1.9.
---------------------------------------------------------------------------
We propose to find that Utah has met the requirement for an
analysis of BART and associated emission reductions achievable at
Hunter and Huntington under 40 CFR 51.308(e)(2)(i)(C).
d. Analysis of Projected Emissions Reductions Achievable Through
the BART Alternative
As discussed previously in section IV.C.4, a summary of Utah's
estimates of emissions for the Utah BART Alternative and the BART
Benchmark is provided in Table 3. We propose to find that Utah has met
the requirement for an analysis of the projected emissions reductions
achievable through the alternative measure under 40 CFR
51.308(e)(2)(i)(D).
e. A Determination That the Alternative Achieves Greater Reasonable
Progress Than Would Be Achieved Through the Installation and Operation
of BART
Greater Reasonable Progress Based on 40 CFR 51.308(e)(3)'s Greater
Emission Reductions Test
As discussed previously in section III.E.1, 40 CFR 51.308(e)(3)
allows a state to satisfy the final step of the better-than-BART
demonstration by showing that that ``distribution of emissions is not
substantially different than under BART'' and that ``the alternative
measure results in greater emission reductions.'' EPA has explained
that when the BART alternative ``achieves greater emission reductions
than each of the individual BART determinations'' \135\ for each of the
pollutants, ``as well as in the aggregate,'' \136\ ``visibility
modeling is not required to support a better-than-BART determination. .
. .'' \137\ However, as EPA explained in responding to comments in the
final rule for the BART Alternative for the Apache Generating Station
in Arizona's SIP, ``where BART and the BART Alternative result in
reduced emissions of one pollutant but increased emissions of another,
it is not appropriate to use the `greater emission reductions' test.''
Instead, the proper approach is to employ a clear weight-of-evidence
approach under 40 CFR 51.308(e)(2) in order to demonstrate that the
alternative achieves greater reasonable progress than BART.'' \138\ We
have not considered a total emissions profile that combines emissions
of multiple pollutants to determine whether BART or the alternative is
``better,'' except where every visibility impairing pollutant is
reduced by a greater amount under the BART alternative.\139\ A
comparison of mass emissions from multiple pollutants (such as
NOX and SO2) is not generally informative,
particularly in assessing whether the alternative approach provides for
greater reasonable progress towards improving visibility. Instead, when
emissions of one or more pollutants increases under an alternative, EPA
has ``given the most weight to the visibility impacts based on air
quality modeling'' \140\ and used modeling to determine whether or not
a ``BART Alternative measure that relies on interpollutant trading
results in greater reasonable progress.'' \141\
---------------------------------------------------------------------------
\135\ 79 FR 9318, 9335 (Feb. 18, 2014).
\136\ 79 FR 9318, 9335 (Feb. 18, 2014). See, e.g., 77 FR 11827,
11837 (Feb. 28, 2012) (proposed approval of Maryland BART
Alternative, which shows greater SO2 and NOX
reductions from the Alternative than application of BART, the two
pollutants covered by the Alternative); 77 FR 39938, 39940-1 (July
6, 2012) (final approval of Maryland BART Alternative, explaining in
responding to comments that because the emission reductions are
greater for the Alternative than BART and the distribution of
emissions is not substantially different, the Alternative was found
to meet 40 CFR 51.308(e)(2) and visibility dispersion modeling was
not needed).
\137\ 79 FR 9318, 9335 (Feb. 18, 2014) (proposed approval of
Arizona BART Alternative for Sundt Unit 4). See also, 79 FR 52420
(Sept. 3, 2014) (final approval of Arizona BART Alternative for
Sundt Unit 4); 77 FR 18052, 18073-18075 (Mar. 26, 2012) (proposed
approval of Colorado BART Alternative, no modeling required where
the 40 CFR 51.308(e)(3) test was met); 77 FR 76871 (Dec. 31, 2012)
(final approval of Colorado BART Alternative).
\138\ 80 FR 19220, 19221 (Apr. 10, 2015). See, e.g., 79 FR
56322, 56327-28 (Sept. 19, 2014); 77 FR 18052, 18075 (Mar. 26.
2012).
\139\ 77 FR 18052, 18075 (Mar. 26, 2012).
\140\ 79 FR 56322, 56328 (Sept. 19, 2014) (proposed approval of
Arizona Apache BART Alternative); 80 FR 19220 (Apr. 10, 2015) (final
approval of Arizona Apache BART Alternative).
\141\ 79 FR 33438, 33441 (June 11, 2014) (final rule, FIP for
Tesoro Refining BART Alternative); See, e.g., 79 FR 56322, 56328
(Sept. 19, 2014) (proposed approval of Arizona Apache BART
Alternative); 80 FR 19220 (Apr. 10, 2015) (final approval of Arizona
Apache BART Alternative); 77 FR 11827, 11837 (Feb. 28, 2012)
(proposed approval of Maryland BART Alternative); 77 FR 39938,
39940-1 (July 6, 2012) (final approval of Maryland BART
Alternative).
---------------------------------------------------------------------------
The State's demonstration appears to satisfy the first part of the
test under 40 CFR 51.308(e)(3) (the distribution of emissions may not
be substantially different than under BART) since the Hunter,
Huntington and Carbon plants are all located within close proximity of
each other in central Utah, as discussed previously in section IV.C.5.
EPA's interpretation of the requirement under 40 CFR 51.308(e)(3) that
the alternative measure ``results in greater emission reductions'' has
been that the emission reduction comparisons are pollutant specific. We
have not looked at a total emissions profile that combines emissions of
multiple pollutants to determine whether a BART benchmark or a BART
alternative is ``better,'' except where every visibility impairing
pollutant is reduced by a greater amount under the BART
alternative.\142\ Therefore, we propose to find that the State's
demonstration does not meet the second part of the test. While in the
aggregate there are fewer SO2 and PM10 emissions
for the BART Alternative, the total NOX emissions are
greater under the BART Alternative than the BART Benchmark. Therefore,
we propose to disapprove Section XX.D.6.c of the Utah SIP under the
test in 40 CFR 51.308(e)(3).
---------------------------------------------------------------------------
\142\ 79 FR 9318, 9335 (Feb. 18, 2014)(proposed approval of
Arizona BART Alternative for Sundt Unit 4). 79 FR 52420 (Sept. 3,
2014) (final approval of Arizona BART Alternative for Sundt Unit 4);
77 FR 18052, 18073-18075 (Mar. 26, 2012) (proposed approval of
Colorado BART Alternative, no modeling required where the 40 CFR
51.308(e)(3) test was met); 77 FR 76871 (Dec. 31, 2012) (final
approval of Colorado BART Alternative).
---------------------------------------------------------------------------
Greater Reasonable Progress Based on 40 CFR 51.308(e)(2)'s Weight-of-
Evidence Test
Utah also chose to conduct a weight-of-evidence analysis under 40
CFR 51.308(e)(2) based on a BART Alternative involving certain units at
the Hunter, Huntington, and Carbon power plants, which included the
following nine categories of evidence.
i. Annual Emissions Comparison of all Visibility-Impairing Pollutants
The emissions of visibility-impairing pollutants from both the Utah
BART Alternative and the BART Benchmark, as estimated by Utah, are
summarized in Table 3 in section IV.C.4. Compared with the Utah BART
Benchmark, the State projects that the Utah BART Alternative will
result in 5,721 tpy more NOX emissions, 8,005 tpy fewer
SO2 emissions and 573 tpy fewer PM10 emissions
than the BART Benchmark. As discussed previously, Utah also
[[Page 2029]]
noted that the combined emissions of NOX, SO2 and
PM10 will be 2,856 tpy lower under the BART Alternative than
the BART Benchmark.
While the total emission reductions under the Utah BART Alternative
are less than those under the BART Benchmark, a comparison of emissions
of multiple pollutant species of emissions is generally not
informative, particularly when the Agency is assessing whether an
approach provides for greater reasonable progress towards improving
visibility. As explained in section VI.B.e, our interpretation of the
language in 40 CFR 51.308(e)(3) (``results in greater emission
reductions . . . may be deemed to achieve greater reasonable
progress'') has been pollutant specific. EPA has not relied on a total
emissions profile that combines emissions of multiple pollutants
together to determine that either BART or a BART alternative is
``better,'' because visibility modeling is the most appropriate method
to assess the overall improvements in visibility impacts from control
scenarios where reductions of multiple pollutants are considered,
except where every visibility impairing pollutant is reduced by a
greater amount under the alternative.\143\ As we have explained,
``[e]ach of the five pollutants which cause or contribute to visibility
impairment has a different impact on light extinction for a given
particle mass, making it therefore extremely difficult to judge the
equivalence of interpollutant trades in a manner that would be
technically credible, yet convenient to implement in the timeframe
needed for transactions to be efficient. This analysis is further
complicated by the fact that the visibility impact that each pollutant
can have varies with humidity, so that control of different pollutants
can have markedly different effects on visibility in different
geographic areas and at different times of the year.'' \144\ As other
Agency actions on BART alternatives have explained, modeling assesses
``both pollutants' chemical aerosol formation mechanisms and impacts on
visibility,'' \145\ which allows evaluation of the ``relative
visibility impacts from the atmospheric formation of visibility
impairing aerosols of sulfate and nitrate.'' \146\ Since we find that
Utah's BART Alternative provides greater emission reductions for two
pollutants (SO2 and PM10), but find that
NOX emissions would be greater under the BART Alternative,
we propose to find that it is not appropriate to combine all three
pollutants in the annual emissions comparison test to support the BART
Alternative as the State has done. While we acknowledge that two of the
pollutants are less under the BART Alternative, one of the pollutants
is greater, therefore we further propose to find that the annual
emissions comparison of all three pollutants does not show that the
BART Alternative is better than the BART Benchmark.
---------------------------------------------------------------------------
\143\ 79 FR 9318, 9335 (Feb. 18, 2014) (proposed approval of
Arizona BART Alternative for Sundt Unit 4). 79 FR 52420 (Sept. 3,
2014) (final approval of Arizona BART Alternative for Sundt Unit 4);
77 FR 18052, 18073-18075 (Mar. 26, 2012) (proposed approval of
Colorado BART Alternative, no modeling required where the 40 CFR
51.308(e)(3) test was met); 77 FR 76871 (Dec. 31, 2012) (final
approval of Colorado BART Alternative).
\144\ 64 FR 35714, 35743 (July 1, 1999).
\145\ 78 FR 79344, 79355 (Dec. 30, 2013).
\146\ 79 FR 33438, 33440 (June 11, 2014).
---------------------------------------------------------------------------
ii. Improvement in the Number of Days With Significant Visibility
Impairment
As discussed previously in section IV.C.5, Utah provided modeling
results to assess the improvement in the number of days with
significant visibility impairment--that is, the improvement in the
number of days with impacts that either cause (>1.0 dv) or contribute
(0.5 dv) to visibility impairment.
The BART Guidelines provide that, when making a BART determination,
a State may consider the number of days or hours that a threshold was
exceeded.\147\ In developing the BART Guidelines, our example modeling
analysis of a hypothetical source examined the number of days that 1.0
dv and 0.5 dv thresholds were exceeded.\148\ As detailed in section
IV.C.5.b, we note the difference in the total number of days impacted--
18 fewer days greater than the causation threshold of 1.0 dv (775 days
for the BART Alternative vs. 793 days for the BART Benchmark), and 175
fewer days greater than the contribution 0.5 dv threshold (1,323 days
for the BART Alternative vs. 1,498 days for the BART Benchmark. Utah's
results show that there are fewer days with impacts over 0.5 dv for the
BART Alternative, which indicates greater improvement in visibility.
Therefore, the results for the 0.5 dv threshold favor the BART
Alternative.
---------------------------------------------------------------------------
\147\ 40 CFR 51, appendix Y, section IV.D.5.
\148\ 70 FR 39130 (July 6, 2005).
---------------------------------------------------------------------------
However, Utah's results for the total number of days with impacts
over 1.0 dv on a Class I area-by-area basis are not as clear in
supporting the BART Alternative. The modeling results for the total
number of days with impacts greater than 1.0 dv show that the BART
Alternative would have more days with impacts greater than 1.0 dv at
seven of the nine Class I areas, and that only two of the Class I
areas, would have fewer days with impacts greater than 1.0 dv compared
to the BART Benchmark. Therefore, the Class I area-by-area results do
not show that the BART Alternative is better than the BART Benchmark.
Similarly, the results for the average number of days with impacts over
1.0 dv show that most of the Class I areas have the same result under
both the BART Alternative and Benchmark, or are within one day of
having the same result. In this context, a difference of one day is not
particularly significant. We therefore propose to find that these
results do not show the BART Alternative is better.
Utah's results in applying the number of days with impacts greater
than 1.0 dv show the BART Alternative is better ``on average'' across
all nine Class I areas. We agree that use of average visibility impacts
could be acceptable as part of assessing the multiple-area impacts and
improvements. However, in this case the visibility results for the
individual Class I areas do not consistently support or undermine the
BART Alternative; there is variation by Class I area. Here, averaging
the visibility results has the effect of obscuring the impacts on the
individual Class I areas. Additionally, we propose to not the give the
difference in days significant weight because by itself it does not
indicate whether benefits on those days were large or small. Therefore,
while we note that the BART Alternative shows fewer days with impacts
greater than 1.0 dv when looking at the average over all nine areas, we
propose to find that averaging the number of days with impacts greater
than 1.0 dv across all affected Class I areas is not a relevant metric
under these circumstances. We therefore further propose to find that
this metric does not show the BART Alternative is better.
iii. 98th Percentile Impact (dv)
As discussed previously in section IV.C.5, Utah asserted that the
only metric it evaluated that showed greater improvement for the BART
Benchmark in comparison to the BART Alternative was the 98th percentile
metric when averaged across all Class I areas and meteorological years
modeled. Utah's comparison of the modeled visibility impacts on the
98th percentile day (8th highest impacted day in a given meteorological
year) for the most impacted year shows that the BART Benchmark would
result in greater visibility improvement at five of the nine Class I
areas, and is better on average across all nine Class I areas (0.11 dv
difference). At the most
[[Page 2030]]
impacted Class I areas, Canyonlands and Capitol Reef, Utah found that
the 98th percentile metric indicates the BART Benchmark has 0.76 dv and
0.57 dv, respectively, more improvement than the BART Alternative. At
other Class I areas, such as Arches, Utah found that the 98th
percentile metric indicates that the BART Alternative provides greater
visibility improvement (for example, 0.44 dv at Flat Tops).
The 98th percentile visibility impact is a key metric recommended
by the BART Guidelines when selecting BART controls.\149\ As noted
previously, we described this metric as an appropriate measure for
determining the degree of visibility improvement to be expected from
controls.\150\ In addition, this is one of the primary metrics that EPA
has relied on in evaluating prior regional haze actions that have
included BART alternatives.\151\
---------------------------------------------------------------------------
\149\ 40 CFR 51, appendix Y, section IV.D.5.
\150\ 70 FR at 39129.
\151\ See, e.g., 78 FR 79344 (Dec. 30, 2012)(proposed rule, FIP
for Tesoro Refining and Intalco Refinery BART Alternatives); 79 FR
33438 (June 11, 2014)(final rule, FIP for Tesoro Refining and
Intalco Refinery BART Alternatives); 79 FR 56322, 56328 (Sept. 19,
2014)(proposed approval of Arizona Apache BART Alternative); 80 FR
19220 (Apr. 10, 2015)(final approval of Arizona Apache BART
Alternative); 77 FR 11827, 11837 (Feb. 28, 2012)(proposed approval
of Maryland BART Alternative); 77 FR 39938, 39940-1 (July 6,
2012)(final approval of Maryland BART Alternative).
---------------------------------------------------------------------------
We note that when calculating visibility improvements for
individual Class I areas, Utah mixed the impacts from different
meteorological years between modeling scenarios (baseline, BART
benchmark, and BART Alternative). As discussed in section V.B.2.e, the
State's use of different meteorological years may introduce some error
as the visibility improvements could be driven by year-to-year
variability in meteorological conditions, as opposed to the differences
in emission reductions between the BART Alternative and BART Benchmark.
For this reason, in addition to the information from the State, EPA has
also calculated the visibility improvements for each modeling scenario
using paired-in-time meteorological and emissions data.\152\ Using this
method, whether the BART Alternative resulted in lower 98th percentile
impacts depends on both the particular Class I area and meteorological
year modeled. In some years and some Class I areas, particularly some
of the most impacted Class I areas, the BART Benchmark shows better
visibility improvement than the BART Alternative (for example, 0.93 dv
greater improvement for Canyonlands and 0.75 in 2002 dv greater
improvement for Capitol Reef in 2001).\153\ At other Class I areas, the
98th percentile metric indicates that the BART Alternative provides
greater visibility improvement (for example, by 0.90 dv at Arches in
2003 and 0.43 dv at Flat Tops in 2002).\154\ On the whole, when using
this method, the BART Benchmark is slightly better on average across
all years and nine Class I areas (0.14 dv difference).\155\ We propose
to find, consistent with the State's evaluation, that this metric
favors the BART Benchmark.
---------------------------------------------------------------------------
\152\ See EPA Calculation of 98th Percentile Improvement for
Utah Bart Alternative spreadsheet (in docket).
\153\ Id.
\154\ Id.
\155\ Id.
---------------------------------------------------------------------------
iv. Annual Average Impact (dv)
As discussed previously in section IV.C.5, Utah's modeling shows
that the average annual dv impact at all Class I areas is better under
the Utah BART Alternative at five of the nine Class I areas, and is
better on average across all the Class I areas. The average impact was
calculated by averaging all daily modeling results for each year and
then calculating a three-year average from the annual average. Utah's
information shows that the BART Alternative is better than the BART
Benchmark by 0.009 dv on average across all nine Class I areas. While
EPA has not considered this metric in the past,\156\ since the State
includes it,\157\ we consider it here. Furthermore, the BART Guidelines
state that, ``in determining what, if any, emission controls should be
required, the State will have the opportunity to consider the
frequency, duration, and intensity of a source's predicted effect on
visibility.'' \158\ We note that the difference in the annual average
metric of 0.009 dv only marginally supports the BART Alternative and
that this metric shows less or equal visibility improvement at four of
the nine Class I areas. Because the annual average metric averages over
all days, it does not represent the benefits of the BART Alternative on
the maximum impact days. In previous evaluations of BART alternatives
we have relied on either the 98th percentile metric or the average
improvement for the worst 20% IMPROVE monitoring days to evaluate
greater reasonable progress. Therefore, we propose to find that the
information from the annual average metric does not support a
conclusion that the BART Alternative achieves greater reasonable
progress than the BART Benchmark.
---------------------------------------------------------------------------
\156\ EPA final actions on BART Alternatives that evaluated
CALPUFF modeling analysis, which did not include consideration of
annual average dv impacts include: 80 FR 19220 (Apr. 10,
2015)(Region 9, Apache); 79 FR 33438 (June 11, 2014)(Region 10,
Tesoro Refining and Alcoa Intalco Operations); 77 FR 39938 (July 6,
2012)(Region 3, Maryland HAA).
\157\ See Utah Regional Haze State Implementation Plan,
Technical Support Document, Ch. 1, p. 23 (2015).
\158\ 70 FR 39121 (July 5, 2005).
---------------------------------------------------------------------------
v. 90th Percentile Impact (dv)
As discussed previously in section IV.C.5, Utah's comparison of the
modeled visibility impacts at the 90th percentile (the 110th highest
day in a year) dv impact shows that the Utah BART Alternative is better
at seven of the nine Class I areas and is slightly better averaged both
across three years and across nine Class I areas (0.006 dv difference).
We note that the use of the 90th percentile impacts to evaluate
alternatives has not been EPA's practice for source-specific BART
determinations; however, as discussed previously for the average dv
impact metric, the BART Guidelines allow states to consider other
visibility metrics in addition to the 98th percentile. Yet, because of
the small difference between the two scenarios (0.006 dv), we propose
to find that it is questionable whether the 90th percentile supports a
conclusion that the BART Alternative achieves greater reasonable
progress.
vi. Timing for the Emissions Reductions
As discussed previously in section IV.C.5, assuming the four BART
units receive five years to come into compliance, Utah noted that
reductions under the Utah BART Alternative will occur earlier than the
BART Benchmark. The reductions under the Utah BART Alternative are
required under the State SIP by August 2015, as noted in Table 5, and
would provide an early and on-going visibility benefit as compared to
BART. Also notable is that combustion control upgrades at the Hunter
and Huntington facilities have been achieving significant
NOX reductions since the time of their installation between
2006 and 2014, depending on the unit.\159\ Finally, if, as proposed in
section VI.C, BART for the four units is LNB/SOFA plus SCR, BART likely
would be fully implemented sometime between 2019 and 2021.
---------------------------------------------------------------------------
\159\ Copies of Administrative Orders DAQE-AN0102370012-08 and
DAQE-AN0102380021-10 are included in the docket, and include
information regarding the schedule for installation of combustion
controls at Hunter and Huntington.
---------------------------------------------------------------------------
Therefore, we recognize that the reductions from the BART
Alternative would occur before the BART Benchmark.
[[Page 2031]]
vii. IMPROVE Monitoring Data
Utah's SIP presents sulfate and nitrate monitoring data at the
Canyonlands IMPROVE monitor that show that ``sulfates are the dominant
visibility impairing pollutant'' \160\ and that sulfate levels have
decreased,\161\ and references similar results at other Class I areas
in the TSD.\162\ Utah also presents data on trends in emissions from
EGUs showing substantial reductions in emissions of both SO2
and NOX.\163\ Based on these data, Utah indicates it ``has
confidence that the SO2 reductions will achieve meaningful
visibility improvement'', under the Utah BART Alternative,\164\ while
``the visibility improvement during the winter months due to
NOX reductions is much more uncertain,'' \165\ Utah makes
this point even though nitrate concentrations are highest in the
winter, explaining that while there has been a reduction in
NOX, the ammonium nitrate values do not show similar
improvement in the winter months. Utah offers several possible
explanations for the results, but does not provide any definitive
conclusions.\166\
---------------------------------------------------------------------------
\160\ Utah Regional Haze State Implementation Plan, Technical
Support Document, Ch. 1, p. 12 (2015).
\161\ Id. at p. 15.
\162\ Id. at p. 12.
\163\ Id. at p. 14.
\164\ Id. at p. 13.
\165\ Id.
\166\ Id. at pp. 16-19.
---------------------------------------------------------------------------
Utah also presents data on the seasonality of park visitation and
monitoring data for nitrate and sulfates. These data show the highest
measured nitrate concentrations occur in winter during the period of
lowest park visitation, and that sulfates affect visibility throughout
the year and are the dominant visibility impairing pollutant from
anthropogenic sources during the high visitation period of March
through November. Utah concludes that it has greater confidence that
reductions in SO2 will be reflected in improved visibility
for visitors to the Class I areas, while reductions in NOX
will have a more uncertain benefit for visitors to Class I areas. We
invite comment on the information and conclusions provided by Utah as
summarized earlier.
We propose to concur with one of the State's findings. We propose
to find that visibility benefits associated with NOX
reductions are much more likely to occur in the winter months because
this is when aerosol thermodynamics favors nitrate formation.\167\ By
contrast, SO2 emissions reductions should provide visibility
benefits in all seasons.\168\ We also propose to find that, as
concluded by the GCVTC, and supported by the IMPROVE monitoring data
presented by Utah, anthropogenic visibility impairment on the Colorado
Plateau is dominated by sulfates. Therefore, we propose to concur with
Utah's statement that sulfate is the largest contributor to visibility
impairment at the affected Class I areas.
---------------------------------------------------------------------------
\167\ Fountoukis, C. & Nenes, A., ISORROPIA II: A
Computationally Efficient Aerosol Thermodynamic Equilibrium Model
for K+, Ca2+,
Mg2+, NH4+,
Na+, SO42-,
NO3-, Cl-, H2O Aerosols,
7 Atmos. Chem. Phys., 4639-4659 (2007).
\168\ Seinfeld, John H., Urban Air Pollution: State of the
Science, 243 Science Magazine, no. 4892, 745, 750 (1989).
---------------------------------------------------------------------------
We propose to disagree with the State's findings related to park
visitation. While the BART Guidelines do mention visitation as
something that can inform a control decision,\169\ EPA is proposing to
place little weight on the State's correlation of emissions reductions
and park visitation because nothing in the CAA suggests that visitors
during busy time periods are entitled to experience better visibility
than visitors during off-peak periods. On the contrary, in the Regional
Haze provisions of the CAA, Congress declared a national goal of
remedying all manmade visibility impairment in all class I areas, which
includes both heavily-visited national parks and seldom-visited
wilderness areas. We invite comment on our evaluation and the
information and conclusions provided by Utah as summarized previously.
---------------------------------------------------------------------------
\169\ 70 FR 39104, 39130 (July 6, 2005) (``Other ways that
visibility improvement may be assessed to inform the control
decisions would be to examine distributions of the daily impacts,
determine if the time of year is important (e.g., high impacts are
occurring during tourist season), consideration of the cost-
effectiveness of visibility improvements (i.e., the cost per change
in deciview), using the measures of deciview improvement identified
by the State, or simply compare the worst case days for the pre- and
post-control runs. States may develop other methods as well.'').
---------------------------------------------------------------------------
viii. Energy and Non-Air Quality Benefits
EPA's evaluation of the State's information on energy and non-air
quality benefits is located earlier in section V.B.2.e.viii.
ix. Cost
EPA's evaluation of the Utah's cost information is located in
section V.B.2.e.ix.
f. Evaluation of the Weight of Evidence
In this section we evaluate Utah's SIP under 40 CFR 51.308(e)(2),
to determine whether the State met the final step of the better-than-
BART analysis ``based on the clear weight of evidence that the trading
program or other alternative measure achieves greater reasonable
progress than would be achieved through the installation and operation
of BART at the covered sources.'' 40 CFR 51.308(e)(2)(i)(E).
As discussed previously, we evaluated Utah's demonstration and all
available information and data presented by the State, as well as
additional information and data EPA developed and presented in this
notice. We propose to find that this information and data do not meet
the requirements of 40 CFR 51.308(e)(2)(i)(E). Specifically, we propose
that Utah's demonstration does not show by the ``clear weight of
evidence'' that the BART alternative ``measure achieves greater
reasonable progress than would be achieved through the installation and
operation of BART at the covered sources.'' 40 CFR 51.308(e)(2)(i)(E).
We have evaluated the relative strengths and weakness of the
information and propose to find that the State's analysis and
conclusions do not clearly show that the BART Alternative results in
greater reasonable progress than the BART Benchmark for the following
reasons: (1) The key metric EPA has used in evaluating alternatives
(98th percentile) on average across all the Class I areas favors the
BART Benchmark by 0.14 dv and not the BART Alternative; (2) the
majority of information and data that the State asserts favor the BART
Alternative over BART show small differences; (3) the comparison of net
emissions reductions across three pollutants, which the State relies on
significantly is not appropriate because not all pollutants are reduced
under the BART Alternative and each pollutant may have different
effects on visibility; and (4) while some information may show the
Alternative is better than BART, the information is not adequate to
meet the ``clear weight of evidence'' test.
First, consistent with the Agency's practice, we have considered
all information, but have given most weight to the visibility impacts
based on air quality modeling.\170\ Here, the 98th percentile impacts
from the State's CALPUFF modeling show that the
[[Page 2032]]
BART Alternative is not better than the BART Benchmark because the BART
Benchmark would provide a 0.14 dv greater average improvement than the
BART Alternative. In addition, Table 12 lists a comparison of 2001-2003
three-year average 98th percentile visibility improvement for each of
the nine Class I areas; and the results for seven of the Class I areas
favor BART over the Alternative (Black Canyon of the Gunnison (0.06
dv), Bryce Canyon (0.04 dv), Canyonlands (0.78 dv), Capitol Reef (0.59
dv), Grand Canyon (0.06 dv), Mesa Verde (0.12 dv), and Zion (0.02 dv)).
---------------------------------------------------------------------------
\170\ See, e.g., 78 FR 79344 (Dec. 30, 2012) (proposed rule, FIP
for Tesoro Refining BART Alternative); 79 FR 33438, 33441 (June 11,
2014) (final rule, FIP for Tesoro Refining BART Alternative); 79 FR
56322, 56328 (Sept. 19, 2014) (proposed approval of Arizona Apache
BART Alternative); 80 FR 19220 (Apr. 10, 2015) (final approval of
Arizona Apache BART Alternative); 77 FR 11827, 11837 (Feb. 28, 2012)
(proposed approval of Maryland BART Alternative); 77 FR 39938,
39940-1 (July 6, 2012) (final approval of Maryland BART
Alternative).
---------------------------------------------------------------------------
Second, several metrics that the State suggests favor the BART
Alternative over BART show only small improvements as compared to BART.
We propose to find that the slight comparative benefits in the annual
average impacts are not compelling evidence that the BART Alternative
will provide for greater reasonable progress than BART. Additionally,
we propose to find that it is questionable whether the 90th percentile
supports a conclusion that the BART Alternative will provide for
greater reasonable progress than BART.
Third, regarding the energy and non-air quality impacts, as well as
cost, for the reasons presented previously, we propose to find that
because these metrics do not have a direct bearing on whether the Utah
BART Alternative achieves greater reasonable progress, it is not
material to our action whether we agree or disagree with Utah's
assessment that they reduce energy and non-air quality impact.
As explained previously in this section, in the aggregate the
SO2 and PM10 emissions are lower for the BART
Alternative. However, the NOX emissions are greater under
the BART Alternative. Additionally, while Utah's results show that some
of the metrics support the Alternative (e.g., there are fewer days with
impacts over 0.5 dv for the Alternative indicating greater improvement
in visibility under the BART Alternative; emission reductions would
occur earlier under the Alternative; the Alternative will result in
8,005 tpy lower SO2 emissions and 573 tpy lower
PM10 emissions compared to the BART Benchmark; sulfate is
the largest contributor to visibility impairment at the affected Class
I areas), we propose to find that these metrics are not enough by
themselves to meet the ``clear weight of evidence'' test.
Thus, we propose to find that the BART Alternative does not meet
the requirements in the RHR because it does not show the BART
Alternative would achieve greater reasonable progress than the BART
Benchmark, and therefore, we are proposing to disapprove the resultant
BART Alternative SIP.
g. Evaluation That Emission Reductions Take Place During Period of
First Long-Term Strategy
EPA's evaluation of Utah's information regarding the timing of
implementation of controls is located in section V.B.2.g.
h. Demonstration That Emission Reductions From Alternative Program Will
Be Surplus
EPA's evaluation of Utah's information regarding whether the
emission reductions are surplus is located in section V.B.2.h.
C. Monitoring, Recordkeeping and Reporting for Utah's BART Alternative
As discussed previously in section IV.B.3, Utah's June 2015 RH SIP
includes enforceable measures and monitoring, recordkeeping and
reporting requirements for the Utah BART Alternative and the State's
PM10 BART determinations. Because in this co-proposal we are
proposing to disapprove Utah's BART Alternative, we are also proposing
to disapprove (in other words, to not make federally enforceable as
part of the SIP) the monitoring, recordkeeping and reporting
requirements located in SIP Sections IX.H.22 associated with the BART
Alternative. This includes SIP Section IX.H.22, subsections a.ii,
a.iii, b.ii, and c.i.
Concurrently, as described earlier in section V.C, we are proposing
to approve the remainder of the monitoring, recordkeeping and reporting
requirements associated with Utah's PM10 BART
determinations. This includes SIP Section IX.H.21 in its entirety and
Section IX.H.22, subsections a.i and b.i.
D. Proposed Federal Implementation Plan
The following explanation details the support for EPA's FIP
proposed in conjunction with the proposed partial approval and partial
disapproval of Utah's SIP. This FIP constitutes EPA's proposed
determination of NOX BART for Utah's four subject-to-BART
sources.
1. BART Evaluations
In determining BART, the state, or EPA if promulgating a FIP, must
consider the five statutory factors in section 169A(g)(2) of the CAA:
(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.
See also 40 CFR 51.308(e)(1)(ii)(A). Our evaluation of BART for Hunter
and Huntington follows the Guidelines for BART Determinations Under the
Regional Haze Rule.
Following the identification of subject-to-BART sources as
described in section IV.A.3, the next step of a BART evaluation is to
perform the BART analysis. The BART Guidelines describe the BART
analysis as consisting of the following five steps: \171\
---------------------------------------------------------------------------
\171\ 40 CFR 51, appendix Y, section IV.D.
---------------------------------------------------------------------------
Step 1: Identify All Available Retrofit Control
Technologies;
Step 2: Eliminate Technically Infeasible Options;
Step 3: Evaluate Control Effectiveness of Remaining
Control Technologies;
Step 4: Evaluate Impacts and Document the Results; and
Step 5: Evaluate Visibility Impacts.
The results of this five step analysis are then used to select
BART, taking into consideration the five factors listed earlier.\172\
---------------------------------------------------------------------------
\172\ See id. section IV.E.
---------------------------------------------------------------------------
Immediately following this, we provide background information that
is common to our cost of compliance analysis (under Step 4) and
visibility impacts analysis (step 5) for all BART sources. This is
followed by the five step analysis and proposed selection of BART
specific to each BART source.
a. Costs of Compliance
In accordance with the BART Guidelines, we have estimated the costs
of compliance consistent with the EPA Air Pollution Control Cost Manual
(CCM).\173\ In addition, we have utilized portions of the draft 2015
revisions to the CCM chapters for the post-combustion NOX
control technologies, selective non-catalytic reduction (SNCR) and
selective catalytic reduction (SCR).\174\ In addition, we rely on the
[[Page 2033]]
cost of compliance estimates supplied to EPA by Andover Technology
Partners (ATP).\175\ These estimates in turn rely on the cost estimates
that PacifiCorp submitted to Utah in 2012 and 2014, but with those cost
estimates adjusted in a number of cases for reasons described in the
ATP report. All costs are presented in 2014 dollars. Refer to the ATP
report and associated spread sheets for details on how the costs of
compliance are calculated.
---------------------------------------------------------------------------
\173\ EPA's CCM Sixth Edition, January 2002, EPA 452/B-02-001.
\174\ Chapter 1, Selective Noncatalytic Reduction, --6/5/2015--
Draft for Public Comment (``the 2015 SNCR CCM''); Chapter 2
Selective Catalytic Reduction, --6/5/2015--Draft for Public Comment
(``the 2015 SCR CCM''). The draft CCM SNCR and SCR revisions were
made available for public comment in a Notice of Data Availability
(NODA) on June 12, 2015, 80 FR 33515, and on July 17, 2015, 80 FR
42491, the public comment period was extended to September 10, 2015.
In this co-proposal for Utah's regional haze SIP, we are not taking
comment on the revisions to the CCM. We are only taking comment on
the application of those revisions of the CCM to the particular
facts and circumstances for the two subject-to-BART sources, Hunter
and Huntington, at issue in this action.
\175\ Cost of NOX BART Controls on Utah EGUs, from
Andover Technology Partners, to EC/R, Inc., October 22, 2015 (ATP
report). Andover Technology Partners is a subcontractor to EC/R
Incorporated.
---------------------------------------------------------------------------
b. Visibility Impact Modeling
The BART Guidelines provide that states may use the CALPUFF
modeling system or another appropriate model to determine the
visibility improvement expected at affected Class I areas from
potential BART control technologies. The BART Guidelines also recommend
that states develop a modeling protocol for modeling visibility
improvement, and suggest that states may want to consult with EPA and
their RPO to address any issues prior to modeling. In consultation with
EPA, Utah developed a CALPUFF modeling protocol titled ``Air Quality
Modeling Protocol: Utah Regional Haze State Implementation Plan'',
February 13, 2015, to support its BART Alternative analysis (see
Chapter 6 of the State's TSD). The Utah protocol follows
recommendations for long-range transport described in appendix W to 40
CFR part 51, Guideline on Air Quality Models, and in the federal
Interagency Workgroup on Air Quality Modeling (IWAQM) Phase 2 Summary
Report and Recommendations for Modeling Long Range Transport Impacts,
as recommended by the BART Guidelines (40 CFR part 51, appendix Y,
section III.D.5). Utah's protocol also follows Federal Land Managers'
Air Quality Related Values Workgroup--Phase I Report (revised 2010). In
section VI.B.e, we evaluate the State's modeling approach in
consideration of the purpose for which it is intended (i.e., analyzing
the BART Alternative). However, because Utah's modeling is not meant to
support analysis of control options for individual BART sources under a
five factor analysis, EPA developed separate CALPUFF modeling for this
purpose. While the Utah modeling assesses the combined impacts of all
of the BART and non-BART sources included in the BART Alternative--
Carbon, Hunter, and Huntington--our modeling assesses the impacts of
the individual BART sources. In addition, our modeling assesses the
visibility impacts of all of the NOX BART control
technologies found to be technologically feasible in Step 2: LNB and
OFA, LNB and OFA with SNCR, and LNB and OFA with SCR. Beyond assessing
impacts from individual BART sources and evaluating all technologically
feasible control options, our modeling methodology is otherwise very
similar to that employed by Utah. Our modeling protocol, and visibility
impact results, can be found in the docket.\176\ Also, the visibility
impacts for each BART source are provided later in the respective five
factor analyses.
---------------------------------------------------------------------------
\176\ Air Quality Modeling Protocol: Utah Regional Haze Federal
Implementation Plan, EPA Region 8, November 2015.
---------------------------------------------------------------------------
EPA notes that, in considering the visibility improvements
reflected in our revised modeling, EPA interprets the BART Guidelines
to require consideration of the visibility improvement from BART
applied to the entire BART-eligible source. The BART Guidelines explain
that, ``[i]f the emissions from the list of emissions units at a
stationary source exceed a potential to emit of 250 tons per year for
any visibility-impairing pollutant, then that collection of emissions
units is a BART-eligible source.'' In other words, the BART-eligible
source (the list of BART emissions units at a source) is the collection
of units for which one must make a BART determination. The BART
Guidelines state ``you must conduct a visibility improvement
determination for the source(s) as part of the BART determination.''
This requires consideration of the visibility improvement from BART
applied to the subject-to-BART source as a whole.
We note, however, that while our regulations require states and EPA
to assess visibility improvement on a source-wide basis, they provide
flexibility to also consider unit-specific visibility improvement in
order to more fully inform the reasonableness of a BART determination,
but that does not replace the consideration of visibility benefit from
the source (facility) as a whole. In making the BART determinations in
this final action we have considered visibility improvements at the
source, and then also at the units that comprise the source.
2. Hunter Power Plant
As described previously in section IV.A, Hunter Units 1 and 2 were
determined to be subject to BART, while Unit 3 is not subject to BART.
Hunter Units 1 and 2 have a nameplate generating capacity of 488.3 MW
each.\177\ The boilers are tangentially fired pulverized coal boilers,
burning bituminous coal from the Deer Creek Mine in Utah.
---------------------------------------------------------------------------
\177\ U.S. Energy Information Administration, Electric
Generating Capacity for 2011 taken from Form EIA-860. See spread
sheet titled ``EIA existing generating units 2011.xls'' in the
docket.
---------------------------------------------------------------------------
Our evaluation of BART for Hunter Units 1 and 2 follows the BART
Guidelines. For Hunter Units 1 and 2, the BART Guidelines are mandatory
because the combined capacity for all three units at the Hunter
facility is greater than 750 MW. See 40 CFR 51.302(e)(1)(ii)(B) (``The
determination of BART for fossil-fuel fired power plants having a total
generating capacity greater than 750 megawatts must be made pursuant to
the guidelines in appendix Y of this part''). Under the Guidelines,
cost estimates for control technologies should be based on the CCM,
where possible.
The BART Guidelines establish presumptive NOX limits for
coal-fired EGUs greater than 200 MW located at greater than 750 MW
power plants that are operating without post-combustion controls. For
the tangential-fired boilers burning bituminous coal at Hunter, that
presumptive limit is 0.28 lb/MMBtu.\178\ The BART Guidelines provide
that the five factor analysis may result in a limit that is different
than the presumptive limit, and the presumptive limits do not obviate
the need to determine BART on a case-by-case basis considering the five
factors.\179\
---------------------------------------------------------------------------
\178\ 40 CFR part 51, appendix Y, IV.E.5, Table. 1.
\179\ See 40 CFR 51.301 (definition of BART); 40 CFR 51.308(e).
---------------------------------------------------------------------------
PacifiCorp provided BART analyses for Hunter Unit 1 to Utah in 2012
and 2014 which we utilize in our proposed BART evaluation here.\180\
Although we are using some information provided by Utah and PacifiCorp,
we are independently evaluating all five statutory BART factors, as is
appropriate for this co-proposed FIP.
---------------------------------------------------------------------------
\180\ PacifiCorp BART Analysis for Hunter Units 1 (July 2,
2012); PacifiCorp BART Analysis for Hunter Unit 2 (June 7, 2012);
Utah's Regional Haze BART Submittal, Chapter 2 of the Technical
Support Document (2015); PacifiCorp's BART Analysis Update for
Hunter Units 1 and 2 and Huntington Units 1 and 2 (Aug. 5, 2014).
---------------------------------------------------------------------------
a. Hunter Unit 1
The Hunter Unit 1 boiler is of tangential-fired design with newer
generation low-NOX burners and separated overfire air which
were installed in 2014. Unit 1 currently achieves an annual emission
rate of approximately 0.21 lb/MMBtu with these combustion controls.
Under Utah's submitted regional haze SIP, Unit 1 is subject to a state-
law NOX emission
[[Page 2034]]
limit of 0.26 lb/MMBtu on a 30-day rolling average. Prior to the
installation of LNB and SOFA the unit operated with an actual annual
emission rate of about 0.40 lb/MMBtu.
Step 1: Identify All Available NOX Control Technologies
In its 2012 BART analysis for Hunter Unit 1, PacifiCorp identified
several NOX control technologies, both for combustion
controls and post-combustion controls.\181\ The combustion controls
identified by PacifiCorp include: low-NOX burners and
separated overfire air (LNB and SOFA; already installed), rotating
overfire air, neural network optimization system, flue gas
recirculation, gas reburn, fuel lean gas reburn, coal switching, water
injection, and others. Post-combustion control options identified by
PacifiCorp include: SNCR, rich reagent injection (RRI), SCR, and
others.
---------------------------------------------------------------------------
\181\ 2012 PacifiCorp BART analysis for Hunter Unit 1, page 2.a-
106.
---------------------------------------------------------------------------
We note that the combustion controls, LNB and SOFA, have already
been installed on Hunter Unit 1, and so we consider them here as ``any
existing controls'' under the third statutory BART factor. In addition,
the BART Guidelines recognize that ``[c]ombinations of inherently
lower-emitting processes and add-on controls'' are a category of
retrofit controls which can be considered.\182\ Accordingly, the
inherently lower-emitting combustion controls, LNB and SOFA, are
evaluated in combination with the add-on controls, SNCR and SCR.
---------------------------------------------------------------------------
\182\ BART Guidelines, IV.D.1.
---------------------------------------------------------------------------
We have reviewed PacifiCorp's review of NOX control
technologies and find it to be comprehensive. We propose to adopt it to
satisfy Step 1 and we refer the reader to the 2012 PacifiCorp BART
analysis for details on the available NOX control
technologies.
Step 2: Eliminate Technically Infeasible Options
In its 2012 BART analysis,\183\ PacifiCorp eliminated available
NOX control technologies that PacifiCorp evaluated as
technologically infeasible for Hunter Unit 1. The remaining
technologically feasible control technologies are the combustion
controls, LNB and SOFA, and the post-combustion controls, SNCR and SCR.
---------------------------------------------------------------------------
\183\ 2012 PacifiCorp BART analysis for Hunter Unit 1, pages
2.a-106 through 2.a-123.
---------------------------------------------------------------------------
We agree with PacifiCorp's evaluation of technologically available
controls for Hunter Unit 1 and propose to adopt it for Step 2.
Step 3: Evaluate Control Effectiveness of Remaining Control
Technologies
As noted previously, Hunter Unit 1 is currently achieving an actual
annual emission rate of approximately 0.21 lb/MMBtu with LNB and SOFA.
This represents a 48.4 percent reduction from the baseline emission
rate of 0.40 lb/MMBtu.
The post-combustion control technologies, SNCR and SCR, have been
evaluated in combination with combustion controls. That is, the inlet
concentration to the post-combustion controls is assumed to be 0.21 lb/
MMBtu (annual). This allows the equipment and operating and maintenance
costs of the post-combustion controls to be minimized based on the
lower inlet NOX concentration.
Typically, SNCR reduces NOX an additional 20 to 30
percent above combustion controls without excessive NH3
slip.\184\ For this analysis, the control efficiency of SNCR has been
calculated based on the formula in the 2015 draft CCM SNCR
chapter,\185\ which for Hunter Unit 1 yields an additional reduction of
21.4 percent after combustion controls. When combined with LNB and
SOFA, SNCR is anticipated to achieve an annual emission rate of 0.16
lb/MMBtu, corresponding to an overall control efficiency of 59.4
percent.
---------------------------------------------------------------------------
\184\ White Paper, SNCR for Controlling NOX
Emissions, Institute of Clean Air Companies, pp. 4 and 9, February
2008.
\185\ 2015 SNCR CCM, Figure 1.1c: SNCR NOX Reduction
Efficiency Versus Baseline NOX Levels for Coal-fired
Utility Boilers.
---------------------------------------------------------------------------
SCR can achieve performance emission rates as low as 0.04 to 0.07
lb/MMBtu on an annual basis.\186\ For this analysis, consistent with
our actions elsewhere, as well with PacifiCorp's analysis, we use an
annual emission rate of 0.05 lb/MMBtu for SCR, which when combined with
LNB and SOFA achieves an overall control efficiency of 87.5 percent.
---------------------------------------------------------------------------
\186\ Srivastava, R., Hall, R., Khan, S., Lani, B., & Culligan,
K., Nitrogen Oxides Emission Control Options for Coal-Fired Utility
Boilers, 55 J. Air & Waste Mgmt. Assoc. 1367, 1367-88 (2005).
---------------------------------------------------------------------------
A summary of emissions projections for the control options
evaluated is provided in Table 13.
Table 13--Summary of NOX BART Analysis Control Technologies for Hunter Unit 1
----------------------------------------------------------------------------------------------------------------
Control
Control option effectiveness Annual emission Emissions Remaining
(%) rate (lb/MMBtu) reduction (tpy) emissions (tpy)
----------------------------------------------------------------------------------------------------------------
LNB/SOFA +SCR........................... 87.5 0.05 5,500 784
LNB/SOFA +SNCR.......................... 59.4 0.16 3,735 2,549
LNB/SOFA................................ 48.4 0.21 3,042 3,242
Baseline\1\............................. ................ 0.40 ................ 6,284
----------------------------------------------------------------------------------------------------------------
\1\ Baseline emissions were determined by averaging the annual emissions from 2001 to 2003 as reported to EPA
Air Markets Program Data, available at http://ampd.epa.gov/ampd/. The annual emissions data is presented in
Chapter 4.a of Utah's June 2015 submittal.
Step 4: Evaluate Impacts and Document Results
Under Step 4, the Guidelines list impact analyses in four parts:
costs of compliance, energy impacts, non-air quality environmental
impacts, and remaining useful life. For convenience, we combine energy
and non-air quality environmental impacts later on.
Part 1--Costs of Compliance
We obtained capital costs for LNB and SOFA from the 2014 PacifiCorp
BART analysis. PacifiCorp did not report any operating and maintenance
costs for LNB and SOFA. Similarly, we obtained capital cost estimates
for LNB and SOFA with SNCR from the 2014 PacifiCorp BART analysis.
However, for operating and maintenance costs we propose to rely on the
draft 2015 draft SNCR chapter of the CCM. Refer to the ATP report for
details. Capital costs for LNB and SOFA with SCR were also obtained
from the 2014 PacifiCorp BART analysis. However, PacifiCorp's capital
costs were adjusted to account for items that were double-counted or
should not be allowed under the CCM, such as an allowance for funds
used during construction (AFUDC).\187\ In
[[Page 2035]]
addition, the capital costs were adjusted to account for a significant
overestimation of the catalyst volume and related costs. These
adjustments are documented in the ATP report and associated spread
sheet. A discussion of operating and maintenance costs of SCR is also
included in the ATP report. For the reasons given in the report, we
propose to adopt the cost estimates contained in it.
---------------------------------------------------------------------------
\187\ See 79 FR 5032, 5133 (Jan. 30, 2014) (discussing reasons
for rejecting use of AFUDC).
---------------------------------------------------------------------------
A summary of our proposed cost estimates for all control options is
presented in Table 14.
Table 14--Summary of NOX BART Costs on Hunter Unit 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average cost
Control option Total capital Indirect annual Direct annual Total annual Emissions effectiveness ($/
investment costs costs cost reductions (tpy) ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB/SOFA.................................... $11.6M $1.2M $0M $1.2M 3,042 $382
LNB/SOFA/SNCR............................... 19.0M 1.9M 1.9M 3.8M 3,735 1,016
LNB/SOFA/SCR................................ 110.3M 10.5M 2.5M 13.1M 5,500 2,380
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parts 2 and 3--Energy and Non-Air Quality Environmental Impacts of
Compliance
SNCR slightly reduces the thermal efficiency of a boiler as the
reduction reaction uses thermal energy from the boiler, decreasing the
energy available for power generation.\188\ Using the CCM, we have
calculated the electrical power consumption of SNCR to be 326,000 kW-hr
per year for Hunter Unit 1.
---------------------------------------------------------------------------
\188\ EPA Air Pollution Control Cost Manual p. 1-21 (6th ed.
2002), available at http://www3.epa.gov/ttncatc1/dir1/c_allchs.pdf.
---------------------------------------------------------------------------
For SCR, the thermal efficiency is much more reduced because the
new ductwork and the reactor's catalyst layers decrease the flue gas
pressure. As a result, additional fan power is necessary to maintain
the flue gas flow rate through the ductwork and reactor. Using the CCM,
we have calculated the electrical power consumption of SCR to be
approximately 18,541,000 kW-hr per year for Hunter Unit 1.
Both SCR and SNCR also require some minimal electricity to service
pretreatment and injection equipment, pumps, compressors, and control
systems. The energy requirements described earlier are not significant
enough to warrant elimination of either SNCR or SCR as BART. In
addition, the cost of the additional energy requirements has been
included in our cost effectiveness calculations.
SNCR and SCR will slightly increase the quantity of ash that will
need to be disposed. In addition, transportation and storage of
chemical reagents may result in spills or releases. However, these non-
air quality environmental impacts do not warrant elimination of either
SNCR or SCR as BART.
There are no additional energy requirements associated with the new
LNB and SOFA, and no significant non-air quality environmental impacts.
In summary, we propose to determine that we have adequately
considered these impacts by including cost of additional energy in cost
effectiveness and assessing non-air quality environmental impacts as
insufficient to eliminate or weigh against any of the BART options.
Part 4--Remaining Useful Life
PacifiCorp assumes a remaining useful life of at least 20 years for
Hunter Unit 1 in its BART analysis, and has not indicated any intention
to retire, or curtail generation from, Hunter Unit 1. Therefore, this
factor does not preclude any of the control options considered. In
addition, this factor is consistent with our BART calculation of cost
effectiveness because annualized costs have been calculated over a 20
year period for each of the control options considered. We propose that
this gives adequate consideration to this factor.
Step 5: Evaluate Visibility Impacts
Table 15 presents the highest of the 98th percentile visibility
improvements at the affected Class I areas for the three meteorological
years modeled, 2001 through 2003. Tables 16 and 17 present the number
of days (summed across three years) with impacts greater than the
contribution and causation thresholds--0.5 dv and 1.0 dv, respectively.
Table 15--Hunter Unit 1--Visibility Improvements
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA and LNB with SOFA and
Class I area ([Delta]dv) SNCR ([Delta]dv) SCR ([Delta]dv)
----------------------------------------------------------------------------------------------------------------
Arches NP.............................................. 0.737 0.906 1.342
Black Canyon of the Gunnison NP........................ 0.198 0.241 0.345
Bryce Canyon NP........................................ 0.306 0.372 0.534
Canyonlands NP......................................... 0.846 1.041 1.545
Capitol Reef NP........................................ 0.639 0.750 1.113
Flat Tops WA........................................... 0.231 0.280 0.404
Grand Canyon NP........................................ 0.349 0.426 0.618
Mesa Verde NP.......................................... 0.235 0.286 0.426
Zion NP................................................ 0.184 0.224 0.323
----------------------------------------------------------------------------------------------------------------
[[Page 2036]]
Table 16--Hunter Unit 1--Days Greater Than 0.5 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA and LNB with SOFA and
Class I area Baseline (days) (days) SNCR (days) SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP........................... 293 260 259 235
Black Canyon of the Gunnison NP..... 68 55 53 41
Bryce Canyon NP..................... 42 37 36 28
Canyonlands NP...................... 359 330 322 311
Capitol Reef NP..................... 175 160 156 145
Flat Tops WA........................ 77 63 59 50
Grand Canyon NP..................... 49 43 42 37
Mesa Verde NP....................... 82 66 63 55
Zion NP............................. 29 23 23 22
----------------------------------------------------------------------------------------------------------------
Table 17--Hunter Unit 1--Days Greater Than 1.0 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA and LNB with SOFA and
Class I area Baseline (days) (days) SNCR (days) SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP........................... 170 141 139 122
Black Canyon of the Gunnison NP..... 22 13 12 9
Bryce Canyon NP..................... 22 19 18 16
Canyonlands NP...................... 240 218 202 188
Capitol Reef NP..................... 118 110 109 94
Flat Tops WA........................ 31 20 18 10
Grand Canyon NP..................... 32 25 23 18
Mesa Verde NP....................... 32 20 19 13
Zion NP............................. 14 9 8 7
----------------------------------------------------------------------------------------------------------------
Select BART.
A summary of our impacts analysis for Hunter Unit 1 is presented in
Table 18.
Table 18--Summary of Hunter Unit 1 Impacts Analysis
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual Total Visibility impacts *
emission Emission annual Average cost Incremental cost -------------------------------------
Control option rate (lb/ reduction costs effectiveness effectiveness ($/ton) Improvement Days > Days >
MMBtu) (tpy) (million$) ($/ton) (dv) 0.5 dv 1.0 dv
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB with SOFA......................... 0.21 3,042 $1.2M $382 ........................ 0.846 330 218
LNB with SOFA and SNCR................ 0.16 3,735 3.8M 1,016 $3,796.................. 1.041 322 202
LNB with SOFA and SCR................. 0.05 5,500 13.1M 2,380 $5,268 (compared to LNB 1.545 311 188
with SOFA and SNCR).
$4,853 (compared to LNB
with SOFA)..
--------------------------------------------------------------------------------------------------------------------------------------------------------
* At the most impacted Class I area, Canyonlands National Park.
In determining what to co-propose as BART, we have taken into
consideration all five of the statutory factors required by the CAA:
The costs of compliance, the energy and non-air quality environmental
impacts of compliance, any existing pollution control technology in use
at the source, the remaining useful life of the source, and the degree
of improvement in visibility which may reasonably be anticipated to
result from the use of such technology. Later we provide a
justification for our selection of BART, including an explanation of
how each of the CAA factors was used in that selection.
As described in step 1 before, we have considered the existing
pollution control technology in use at the source. We note that Hunter
Unit 1 was equipped with LNB and SOFA in the spring of 2014 in order to
meet state-law requirements in the 2011 Utah RH SIP submittal, which we
did not approve. In this co-proposal we have to evaluate control
technologies and baseline emissions from the correct starting point,
that is, prior to the installation of the combustion controls pursuant
to state-law NOX limitations.\189\ As a result, we used the
period 2001-2003 as the appropriate period for baseline emissions, in
order to provide a realistic depiction of annual emissions for Hunter
Unit 1 prior to installation of combustion controls.
---------------------------------------------------------------------------
\189\ See 79 FR 5032, 5105 (Jan. 30, 2014).
---------------------------------------------------------------------------
We have considered the energy and non-air quality environmental
impacts of compliance and propose to find that
[[Page 2037]]
they do not appreciably favor one control option over another, or
preclude a particular control option from selection. And finally, we
have considered the remaining useful life of the source and find that
it is sufficiently long (greater than 20 years) so as not to favor or
preclude any of the control options. As a result, the remaining
factors--the costs of compliance and visibility improvement--are the
primary factors that lead us to our proposed BART selection for Hunter
Unit 1.
In order to select BART we propose to consider the costs of
compliance and visibility impacts by generally comparing them with BART
determinations that have been made elsewhere. In the context of
reasonable progress determinations, a comparison with another
reasonable progress determination has been upheld by the Ninth Circuit
Court of Appeals as a rational explanation for that determination.\190\
If this were the first BART determination under the RHR and BART
Guidelines, which it is not, it would obviously be difficult to employ
this precise methodology.\191\ At this point, however, the EPA thinks
there are sufficient examples of reasonable determinations to make this
methodology feasible.
---------------------------------------------------------------------------
\190\ Nat'l Parks Conserv. Ass'n v. U.S. EPA, 788 F.3d 1134,
1148-49 (9th Cir. 2014).
\191\ Even in that initial scenario, at least cost of
compliance, as expressed in cost-effectiveness in dollars per ton,
can be compared with what has been found reasonable for best
available control technology (BACT) and reasonably available control
technology (RACT), and visibility improvement can be compared with
the 0.5 dv subject-to-BART threshold that determines whether a BART-
eligible source causes or contributes to visibility impairment in
Class I areas. The EPA notes that this alternate methodology would
also support our proposed BART determinations in this action.
---------------------------------------------------------------------------
Specifically, we propose to compare the average cost-effectiveness,
incremental cost-effectiveness, visibility improvement, and incremental
visibility improvement for LNB and SOFA with SCR with BART
determinations where the EPA and States have based their determination
on the same metrics. The most comparable determination appears to be in
EPA's final action for Wyoming's regional haze SIP, in which EPA
promulgated a FIP for three units at Laramie River Station and
determined NOX BART to be LNB and SOFA with SCR for the
three units.\192\ On a per-unit basis, the visibility improvement at
the most impacted Class I area from this control option was 0.52 to
0.57 dv, and across all three units the sum of the improvement was 1.62
dv. Thus, the application of this control option to all three units of
Laramie River Station was estimated to have a visibility benefit about
the same as the application of this control option to Hunter Unit 1.
The average cost-effectiveness ranged from $4,375/ton to $4,461/ton,
considerably higher than the corresponding value for Hunter Unit 1,
while the incremental cost-effectiveness ranged from $5,449 to $5,871/
ton which is very close to the corresponding value for Hunter Unit 1.
Finally, the incremental visibility improvement as compared to LNB and
SOFA with SNCR was significant, as it is for Hunter Unit 1. On the
other hand, at Dave Johnston Units 3 and 4 (for example), where EPA
rejected LNB and SOFA with SCR, the incremental cost-effectiveness
value of LNB and SOFA with SCR was much higher and incremental
visibility benefit lower than at Laramie River Station and higher than
the same metrics at Hunter Unit 1.\193\
---------------------------------------------------------------------------
\192\ 79 FR 5032, 5047 (Jan. 30, 2014).
\193\ 79 FR 5032, 5049.
---------------------------------------------------------------------------
There are other BART determinations in which SCR has been selected
as BART (either alone or in conjunction with LNB and SOFA) based on
similar metrics, although those determinations may not have explicitly
discussed incremental cost-effectiveness and incremental visibility
benefits on a per-unit basis. First, the State of Colorado selected,
and the EPA approved, SCR as NOX BART for Public Service
Company's Hayden Station, Units 1 and 2.\194\ Hayden Units 1 and 2 were
equipped with first generation LNB and over-fire air (OFA) installed in
1999.\195\ In its BART determination, Colorado considered these
existing controls as given and analyzed as feasible controls upgraded
LNB, SNCR, and SCR. Based on an average cost-effectiveness of $3,385/
ton and $4,064/ton, incremental cost-effectiveness (as compared with
LNB and OFA with SNCR) of $5,326/ton and $7,331/ton, and visibility
improvement of 1.12 dv and 0.85 dv at the most impacted Class I area,
respectively, Colorado selected SCR as BART for Units 1 and 2. In this
case, due to the existing controls at Hayden Station, the cost-
effectiveness values for SCR for Hayden Units 1 and 2 should be
compared to the incremental cost-effectiveness values (as compared with
LNB and SOFA, and with LNB and SOFA with SNCR) for SCR for Hunter Unit
1, and similarly for incremental visibility benefits. We think they are
comparable, particularly for Hayden Unit 2, and considering that Hunter
Unit 1 significantly impacts several Class I areas, while Colorado
selected SCR for Hayden based solely on the visibility improvement at
the most impacted Class I area, Mt. Zirkel Wilderness.
---------------------------------------------------------------------------
\194\ 77 FR 18069 (Mar. 26, 2012) (proposal); 77 FR 76871 (Dec.
31, 2012) (final).
\195\ Colorado Department of Health and Environment, Air
Pollution Control Division, Best Available Retrofit Technology
(BART) Analysis of Control Options For Public Service Company--
Hayden Station, p. 5, available at https://www.colorado.gov/pacific/sites/default/files/AP_PO_Hayden-Power-Plant_0.pdf.
---------------------------------------------------------------------------
Another comparable determination can be found in EPA's FIP for
Arizona Public Service's Cholla Power Plant, Units 2, 3, and 4, in
which EPA determined that NOX BART was SCR.\196\ Similarly
to Colorado's determination for Hayden, EPA considered the existing
controls, LNB and OFA, at the three units and estimated average cost-
effectiveness values for SCR of $3,114/ton, $3,472/ton, and $3,395/ton,
and incremental cost-effectiveness values (as compared to LNB and OFA
with SNCR) of $3,257/ton, $3,811/ton, and $3,661/ton, respectively, for
Units 2, 3, and 4. EPA's modeling showed a source-wide visibility
improvement for SCR of 1.34 dv at the most impacted Class I area. Based
on these metrics, EPA determined NOX BART to be SCR for the
three units. In this case, as with Hayden, the average cost-
effectiveness of SCR at Cholla should be compared with the incremental
cost-effectiveness of SCR (as compared with just LNB and SOFA) at
Hunter Unit 1. The cost-effectiveness values for Hunter Unit 1 are
somewhat higher than at Cholla, but on the other hand the source-wide
visibility improvement at Hunter Units 1 and 2 (as obtained by summing
the per-unit improvements from Units 1 and 2) \197\ from LNB and SOFA
with SCR is 2.759 dv at the most impacted Class I area, with
incremental visibility improvements of 1.29 dv and 0.932 dv over LNB
and SOFA and LNB and SOFA with SNCR, respectively. These visibility
improvements are very much in line with those at Cholla, and given that
the incremental cost-effectiveness of SCR at Hunter Unit 1 is still
reasonable, the comparison with Cholla also supports selection of SCR
for Hunter Unit 1. We invite comment on other potentially relevant BART
determinations and our methodology generally.
---------------------------------------------------------------------------
\196\ 77 FR 42834 (July 20, 2012) (proposal); 77 FR 72512,
72514-15 (Dec. 5, 2012) (final).
\197\ We use the source-wide number here to compare with the
Cholla determination; in addition as explained above we must
consider source-wide visibility improvements.
---------------------------------------------------------------------------
Based on these comparisons to Laramie River Station, Hayden
Station, Dave Johnston Units 3 and 4, and Cholla Power Plant, we think
that selection of LNB and SOFA with SCR as BART for Hunter Unit 1 would
be fully consistent with these prior actions. For Hunter
[[Page 2038]]
Unit 1, LNB and SOFA with SCR is very cost-effective, at $2,380/ton on
an average basis (counting the costs and emission reductions from the
combination of the three control technology elements) and at $5,268/ton
on an incremental basis compared to LNB with SOFA and SNCR. Compared to
LNB with SOFA, the incremental cost effectiveness is $4,813/ton, which
also compares favorably to the incremental cost effectiveness that
supported the selection of LNB with SOFA and SCR for Laramie River
Station. For Hunter Unit 1, LNB and SOFA with SCR provides substantial
visibility benefits at several Class I areas that are similar to those
from Laramie River Station and larger than those from Dave Johnson
Units 3 and 4. For example, the visibility improvement from that
control option installed on a single unit is 1.342 dv at Arches NP,
1.545 dv at Canyonlands NP, and 1.113 at Capitol Reef NP. These
comparisons show that costs are justified in light of the substantial
visibility benefits, both total and incremental.
In the case of Hunter, the unit level visibility improvements
justify the most stringent level of control, SCR, for each of the two
Hunter units. Necessarily, when we consider the source-wide visibility
improvements, they will be larger and also justify the most stringent
level of control. In addition, the unit level visibility improvements
and source-wide visibility improvements (as derived by summing the unit
level visibility improvements) at other impacted Class I areas,
particularly Arches NP and Capitol Reef NP, support the most stringent
level of control. Accordingly, for Hunter Unit 1, we propose to find
that BART for NOX is LNB and SOFA with SCR, represented by
an emission limit of 0.07 lb/MMBtu (30-day rolling average). The
proposed BART emission limit of 0.07 lb/MMBtu allows for a sufficient
margin of compliance for a 30-day rolling average limit that would
apply at all times, including startup, shutdown, and malfunction.\198\
We are also proposing monitoring, recordkeeping, and reporting
requirements as described in our proposed regulatory text for 40 CFR
52.2336.
---------------------------------------------------------------------------
\198\ Emission limits such as BART are required to be met on a
continuous basis. See 70 FR 39104, 39172 (July 6, 2005) (stating
that emissions limits including BART are to be met on a ``continuous
basis'' in the BART Guidelines, section V); 42 U.S.C. 7602(k)
(noting that emission limits are to be on ``a continuous basis'').
---------------------------------------------------------------------------
Under 40 CFR 51.308(e)(1)(iv), ``each source subject to BART [is]
required to install and operate BART as expeditiously as practicable,
but in no event later than five years after approval of the
implementation plan revision.'' In light of the considerable effort
involved to retrofit SCR, we propose that five years is as
expeditiously as practicable. Therefore, we propose a compliance
deadline of five years from the date our final FIP becomes effective.
b. Hunter Unit 2
Generally speaking, Hunter Unit 2 is identical to Hunter Unit 1.
The Hunter Unit 2 boiler is of tangential-fired design with newer
generation low-NOX burners and separated overfire air which
were installed in spring 2011. Hunter Unit 2 currently achieves an
annual emission rate of approximately 0.20 lb/MMBtu with these
combustion controls. Under Utah's submitted regional haze SIP, Unit 1
is subject to a state-law NOX emission limit of 0.26 lb/
MMBtu on a 30-day rolling average. Prior to the installation of LNB and
SOFA the unit operated with an actual annual emission rate of about
0.38 lb/MMBtu.
Step 1: Identify All Available NOX Control Technologies
For the same reasons as for Hunter Unit 1, we propose to adopt the
identification of available NOX control technologies in
PacifiCorp's 2012 BART analysis to satisfy Step 1, and we refer the
reader to the 2012 PacifiCorp BART analysis for details on those
control technologies.
Step 2: Eliminate Technically Infeasible Options
In its 2012 BART analysis,\199\ PacifiCorp eliminated available
NOX control technologies that PacifiCorp evaluated as
technologically infeasible for Hunter Unit 2. The remaining
technologically feasible control technologies are the combustion
controls, LNB and SOFA, and the post-combustion controls, SNCR and SCR.
---------------------------------------------------------------------------
\199\ PacifiCorp BART Analysis for Hunter Unit 2, pp. 2.b-105--
2.a-122 (2012).
---------------------------------------------------------------------------
As with Hunter Unit 1, we agree with PacifiCorp's evaluation of
technologically available controls for Hunter Unit 2 and propose to
adopt it for Step 2.
Step 3: Evaluate Control Effectiveness of Remaining Control
Technologies
As noted previously, Hunter Unit 2 is currently achieving an actual
annual emission rate of approximately 0.20 lb/MMBtu with LNB and SOFA.
This represents a 48.2 percent reduction from the baseline emission
rate of 0.38 lb/MMBtu.
SCR can achieve performance emission rates as low as 0.04 to 0.07
lb/MMBtu on an annual basis.\200\ For this analysis, consistent with
our actions elsewhere, as well with PacifiCorp's analysis, we use an
annual emission rate of 0.05 lb/MMBtu for SCR, which when combined with
LNB and SOFA achieves an overall control efficiency of 86.9 percent.
For this analysis, consistent with our actions elsewhere, as well with
PacifiCorp's analysis, we use an annual emission rate of 0.05 lb/MMBtu
for SCR, which when combined with LNB and SOFA achieves an overall
control efficiency of 86.9 percent.
---------------------------------------------------------------------------
\200\ Srivastava, R., Hall, R., Khan, S., Lani, B., & Culligan,
K., Nitrogen Oxides Emission Control Options for Coal-Fired Utility
Boilers, 55 J. Air & Waste Mgmt. Assoc. 1367, 1385-86 (2005).
---------------------------------------------------------------------------
As with Hunter Unit 1, we evaluated post-combustion control
technologies, SNCR and SCR, in combination with combustion controls.
Our evaluation is the same as for Hunter Unit 1. A summary of emissions
projections for the control options evaluated is provided in Table 19.
Table 19--Summary of NOX BART Analysis Control Technologies for Hunter Unit 2
----------------------------------------------------------------------------------------------------------------
Control Annual emission Emissions Remaining
Control option effectiveness (%) rate (lb/MMBtu) reduction (tpy) emissions (tpy)
----------------------------------------------------------------------------------------------------------------
LNB/SOFA+SCR........................ 86.9 0.05 5,230 788
LNB/SOFA+SNCR....................... 59.2 0.16 3,562 2,457
LNB/SOFA............................ 48.2 0.20 2,902 3,117
Baseline \1\........................ ................. 0.38 ................. 6,018
----------------------------------------------------------------------------------------------------------------
\1\ Baseline emissions were determined by averaging the annual emissions from 2001 to 2003 as reported to EPA
Air Markets Program Data available at http://ampd.epa.gov/ampd/.
[[Page 2039]]
Step 4: Evaluate Impacts and Document Results
Part 1--Costs of Compliance
We obtained capital costs for LNB and SOFA from the 2014 PacifiCorp
BART analysis. PacifiCorp did not report any operating and maintenance
costs for LNB and SOFA. Similarly, we obtained capital cost estimates
for LNB and SOFA with SNCR from the 2014 PacifiCorp BART analysis.
However, for operating and maintenance costs we propose to rely on the
draft 2015 draft SNCR chapter of the CCM. Refer to the ATP report for
details. Capital costs for LNB and SOFA with SCR were also obtained
from the 2014 PacifiCorp BART analysis. However, PacifiCorp's capital
costs were adjusted to account for items that were double-counted or
should not be allowed under the CCM, such as AFUDC.\201\ In addition,
the capital costs were adjusted to account for a significant
overestimation of the catalyst volume and related costs. These
adjustments are documented in the ATP report and associated spread
sheet. A discussion of operating and maintenance costs of SCR is also
included in the ATP report. For the reasons given in the report, we
propose to adopt the cost estimates contained in it.
---------------------------------------------------------------------------
\201\ See 79 FR 5032, 5133 (Jan. 30, 2014) (discussing reasons
for rejecting use of AFUDC).
---------------------------------------------------------------------------
A summary of our proposed cost estimates for all control options is
presented in Table 20.
Table 20--Summary of NOX BART Costs on Hunter Unit 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average cost
Control option Total capital Indirect annual Direct annual Total annual cost Emissions effectiveness ($/
investment cost cost reductions (tpy) ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB/SOFA.............................. $8.6M $0.9M $0M $0.9M 2,902 $298
LNB/SOFA/SNCR......................... 16.0M 1.6M 1.9M 3.5M 3,562 968
LNB/SOFA/SCR.......................... 108.1M 10.3 2.4M 12.7M 5,230 2,432
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parts 2 and 3--Energy and Non-Air Quality Environmental Impacts of
Compliance
The energy and non-air quality impacts for Hunter Unit 2 are nearly
identical to those for Hunter Unit 1 as discussed previously.
Accordingly, for the same reasons as for Hunter Unit 1, we propose to
determine that we have adequately considered these impacts by including
cost of additional energy in cost effectiveness and assessing non-air
quality environmental impacts as insufficient to eliminate or weigh
against any of the BART options.
Part 4--Remaining Useful Life
PacifiCorp assumes a remaining useful life of at least 20 years for
Hunter Unit 2 in its BART analysis, and has not indicated any intention
to retire, or curtail generation from, Hunter Unit 2. Therefore, this
factor does not preclude any of the control options considered. In
addition, this factor is consistent with our BART calculation of cost
effectiveness because annualized costs have been calculated over a 20
year period for each of the control options considered. We propose that
this gives adequate consideration to this factor.
Step 5: Evaluate Visibility Impacts
Table 21 presents the highest of the 98th percentile visibility
improvements at the affected Class I areas for the three meteorological
years modeled, 2001 through 2003. Tables 22 and 23 present the number
of days (summed across three years) with impacts greater than the
contribution and causation thresholds--0.5 dv and 1.0 dv, respectively.
Table 21--Hunter Unit 2--Visibility Improvements
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA and LNB with SOFA and
Class I area ([Delta]dv) SNCR ([Delta]dv) SCR ([Delta]dv)
----------------------------------------------------------------------------------------------------------------
Arches NP.............................................. 0.569 0.711 1.080
Black Canyon of the Gunnison NP........................ 0.153 0.189 0.279
Bryce Canyon NP........................................ 0.234 0.291 0.429
Canyonlands NP......................................... 0.658 0.822 1.250
Capitol Reef NP........................................ 0.491 0.623 0.879
Flat Tops WA........................................... 0.180 0.223 0.328
Grand Canyon NP........................................ 0.275 0.340 0.506
Mesa Verde NP.......................................... 0.182 0.225 0.344
Zion NP................................................ 0.144 0.178 0.262
----------------------------------------------------------------------------------------------------------------
Table 22--Hunter Unit 2--Days Greater Than 0.5 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA and LNB with SOFA and
Class I area Baseline (days) (days) SNCR (days) SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP........................... 293 276 268 245
Black Canyon of the Gunnison NP..... 68 57 55 49
Bryce Canyon NP..................... 42 39 37 30
Canyonlands NP...................... 359 336 331 317
Capitol Reef NP..................... 175 163 161 152
[[Page 2040]]
Flat Tops WA........................ 77 64 63 57
Grand Canyon NP..................... 49 46 45 40
Mesa Verde NP....................... 82 72 66 59
Zion NP............................. 29 24 23 22
----------------------------------------------------------------------------------------------------------------
Table 23--Hunter Unit 2--Days Greater Than 1.0 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA and LNB with SOFA and
Class I area Baseline (days) (days) SNCR (days) SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP........................... 170 151 145 131
Black Canyon of the Gunnison NP..... 22 16 13 11
Bryce Canyon NP..................... 22 21 19 16
Canyonlands NP...................... 240 221 218 198
Capitol Reef NP..................... 118 113 111 105
Flat Tops WA........................ 31 20 20 14
Grand Canyon NP..................... 32 25 25 22
Mesa Verde NP....................... 32 22 20 14
Zion NP............................. 14 11 9 8
----------------------------------------------------------------------------------------------------------------
Select BART.
A summary of our impacts analysis for Hunter Unit 2 is presented in
Table 24.
Table 24--Summary of Hunter Unit 2 Impacts Analysis
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual Total Visibility impacts *
emission Emission annual Average cost Incremental cost -------------------------------------
Control option rate (lb/ reduction costs effectiveness effectiveness ($/ton) Improvement Days > Days >
MMBtu) (tpy) (million$) ($/ton) (dv) 0.5 dv 1.0 dv
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB with SOFA........................ 0.20 2,902 $0.9M $298 ....................... 0.658 336 221
LNB with SOFA and SNCR............... 0.16 3,562 3.5M 968 $3,913................. 0.822 331 218
LNB with SOFA and SCR................ 0.05 5,230 12.7M 2,432 $5,558 (compared to LNB 1.250 317 198
with SOFA and SNCR).
$5,092 (compared to LNB
with SOFA)..
--------------------------------------------------------------------------------------------------------------------------------------------------------
* At the most impacted Class I area, Canyonlands National Park.
In determining what to co-propose as BART, we have taken into
consideration all five of the statutory factors required by the CAA:
The costs of compliance, the energy and non-air quality environmental
impacts of compliance, any existing pollution control technology in use
at the source, the remaining useful life of the source, and the degree
of improvement in visibility which may reasonably be anticipated to
result from the use of such technology. Later on we provide a
justification for our selection of BART, including an explanation of
how each of the CAA factors was used in that selection.
We have considered the energy and non-air quality environmental
impacts of compliance and propose to find that they do not appreciably
favor one control option over another, or preclude a particular control
option from selection. As explained for Hunter Unit 1, the existing
pollution controls have been accounted for in our evaluation of BART,
and also would not favor or preclude any of the control options
considered. And finally, we have considered the remaining useful life
of the source and find that it is sufficiently long (greater than 20
years) so as not to favor or preclude any of the control options. As a
result, the remaining factors--the costs of compliance and visibility
improvement--are the primary factors that lead us to our proposed BART
selection for Hunter Unit 2.
In order to select BART we propose (for the same reasons as for
Hunter Unit 1) to weigh the costs of compliance against visibility
impacts by generally comparing them with BART determinations that have
been made elsewhere. Specifically, we propose to compare the average
cost-effectiveness, incremental cost-effectiveness, visibility
improvement, and incremental visibility improvement for LNB and SOFA
with SCR with BART determinations where the EPA and States have based
their determination on the same metrics. The most comparable
determinations are the same as for Hunter Unit 1: Laramie River
Station, Hayden Station, and Cholla Power Plant.
[[Page 2041]]
Based on these comparisons, we think LNB and SOFA with SCR for
Hunter 2 is fully consistent with the other BART determinations. LNB
and SOFA with SCR is very cost-effective at $2,432/ton, and provides
substantial visibility benefits at several Class I areas. For example,
the visibility improvement from that control option is 1.250 dv at
Canyonlands NP and 1.080 dv at Arches NP. The incremental cost-
effectiveness of SCR, $5,558/ton, is by comparison also reasonable.
This comparison also shows that costs are justified in light of the
substantial visibility benefits, both total and incremental.
In the case of Hunter, the unit level visibility improvements
justify the most stringent level of control, SCR, for each of the two
Hunter units. Necessarily, when we consider the source-wide visibility
improvements, they will be larger and also justify the most stringent
level of control. In addition, the unit level visibility improvements
and source-wide visibility improvements (as derived by summing the unit
level visibility improvements) at other impacted Class I areas,
particularly Arches NP and Capitol Reef NP, support the most stringent
level of control.
Accordingly, for Hunter Unit 2, we propose to find that BART for
NOX is LNB and SOFA with SCR, represented by an emission
limit of 0.07 lb/MMBtu (30-day rolling average). The proposed BART
emission limit of 0.07 lb/MMBtu allows for a sufficient margin of
compliance for a 30-day rolling average limit that would apply at all
times, including startup, shutdown, and malfunction.\202\ We are also
proposing monitoring, recordkeeping, and reporting requirements as
described in our proposed regulatory text for 40 CFR 52.2336.
---------------------------------------------------------------------------
\202\ Emission limits such as BART are required to be met on a
continuous basis. See 70 FR 39104, 39172 (July 6, 2005) (stating
that emissions limits including BART are to be met on a ``continuous
basis'' in the BART Guidelines, section V); 42 U.S.C. 7602(k)
(noting that emission limits are to be on ``a continuous basis'').
---------------------------------------------------------------------------
Under 40 CFR 51.308(e)(1)(iv), ``each source subject to BART [is]
required to install and operate BART as expeditiously as practicable,
but in no event later than 5 years after approval of the implementation
plan revision.'' In light of the considerable effort involved to
retrofit SCR, we propose that five years is as expeditiously as
practicable. Therefore, we propose a compliance deadline of five years
from the date our final FIP becomes effective.
3. Huntington Power Plant
As described previously in section IV.A, Huntington Units 1 and 2
were determined to be subject to BART. PacifiCorp's Huntington Power
Plant (Huntington), is located in Huntington City, Utah, and consists
of a total of the two electric utility steam generating units.
Huntington Units 1 and 2 have a nameplate generating capacity of 498 MW
each.\203\ The boilers are tangentially fired pulverized coal boilers,
burning bituminous coal from the nearby Deer Creek Mine.
---------------------------------------------------------------------------
\203\ See U.S. Energy Information Administration, Electric
Generating Capacity for 2011 (taken from Form EIA-860). See ``EIA
existing generating units 2011.xls'' spreadsheet in the docket.
---------------------------------------------------------------------------
Our evaluation of BART for Huntington Unit 1 and 2 follows the
Guidelines for BART Determinations Under the Regional Haze Rule, which
are found in appendix Y to 40 CFR part 51. For Huntington Units 1 and
2, the BART Guidelines are mandatory because the combined capacity for
all units at the Huntington facility is greater than 750 MW.\204\ Under
the Guidelines, cost estimates for control technologies should be based
on the CCM, where possible.
---------------------------------------------------------------------------
\204\ See 40 CFR 51.302(e)(1)(ii)(B) (``The determination of
BART for fossil-fuel fired power plants having a total generating
capacity greater than 750 megawatts must be made pursuant to the
guidelines in appendix Y of this part.'').
---------------------------------------------------------------------------
The BART Guidelines establish presumptive NOX limits for
coal-fired EGUs greater than 200 MW located at greater than 750 MW
power plants that are operating without post-combustion controls. For
the tangential-fired boilers burning bituminous coal at Huntington,
that presumptive limit is 0.28 lb/MMBtu.\205\ The BART Guidelines
provide that the five factor analysis may result in a limit that is
different than the presumptive limit, and the presumptive limits do not
obviate the need to determine BART on a case-by-case basis considering
the five factors.\206\
---------------------------------------------------------------------------
\205\ 40 CFR part 51, appendix Y, IV.E.5, Table. 1.
\206\ See 40 CFR 51.301 (defining BART); 40 CFR 51.308(e).
---------------------------------------------------------------------------
PacifiCorp provided BART analyses for Huntington 1 and 2 to Utah in
2012 and 2014 which we utilize in our proposed BART evaluation
here.\207\ Although we are using some information provided by Utah and
PacifiCorp, we have independently evaluated all five statutory BART
factors.
---------------------------------------------------------------------------
\207\ See PacifiCorp BART Analysis for Huntington Unit 1(2012);
PacifiCorp BART Analysis for Huntington Unit 2 (2012); see also
Chapter 2 of the Technical Support Document for Utah's Regional Haze
BART Submittal; PacifiCorp's BART Analysis Update for Hunter Units 1
and 2 and Huntington Units 1 and 2 (2014).
---------------------------------------------------------------------------
a. Huntington Unit 1
The Huntington Unit 1 boiler is of tangential-fired design with
newer generation low-NOX burners and separated overfire air
which were installed in fall 2010. Huntington Unit 1 currently achieves
an annual emission rate of approximately 0.22 lb/MMBtu with these
combustion controls. Under Utah's submitted regional haze SIP, Unit 1
is subject to a state-law NOX emission limit of 0.26 lb/
MMBtu on a 30-day rolling average. Prior to the installation of LNB and
SOFA the unit operated with an actual annual emission rate of about
0.37 lb/MMBtu.
Step 1: Identify All Available NOX Control Technologies
In its 2012 BART analysis for Huntington Unit 1, PacifiCorp
identified several NOX control technologies, both for
combustion controls and post-combustion controls.\208\ The combustion
controls identified by PacifiCorp include: Low-NOX burners
and separated overfire air (LNB and SOFA overfire air; already
installed), rotating overfire air, neural network optimization system,
flue gas recirculation, gas reburn, fuel lean gas reburn, coal
switching, water injection, and others. Post-combustion control options
identified by PacifiCorp include: SNCR, RRI, SCR, and others.
---------------------------------------------------------------------------
\208\ PacifiCorp BART Analysis for Huntington Unit 1, p. 2.c-60
(2012).
---------------------------------------------------------------------------
We note that the combustion controls, LNB and SOFA, have already
been installed on Huntington Unit 1, and so we consider them here as
``any existing controls'' under the third statutory factor. In
addition, the BART Guidelines recognize that ``[c]ombinations of
inherently lower-emitting processes and add-on controls'' are a
category of retrofit controls which can be considered.\209\
Accordingly, the inherently lower-emitting combustion controls, LNB and
SOFA, are evaluated in combination with the add-on controls, SNCR and
SCR.
---------------------------------------------------------------------------
\209\ 40 CFR part 51 appendix Y.
---------------------------------------------------------------------------
We have reviewed PacifiCorp's review of NOX control
technologies and find it to be comprehensive. We propose to adopt it to
satisfy Step 1 and we refer to the 2012 PacifiCorp BART analysis for
details on the available NOX control technologies.
Step 2: Eliminate Technically Infeasible Options
In its 2012 BART analysis,\210\ PacifiCorp eliminated available
NOX control technologies that PacifiCorp evaluated as
technologically infeasible for Huntington Unit 1. The remaining
technologically feasible control technologies are the combustion
[[Page 2042]]
controls, LNB and SOFA, and the post-combustion controls, SNCR and SCR.
---------------------------------------------------------------------------
\210\ PacifiCorp BART Analysis for Huntington Unit 1, pp. 2.c-
61--2.c-77 (2012).
---------------------------------------------------------------------------
We agree with PacifiCorp's evaluation of technologically available
controls for Huntington Unit 1 and propose to adopt it for Step 2.
Step 3: Evaluate Control Effectiveness of Remaining Control
Technologies
As noted previously, Huntington Unit 1 is currently achieving an
actual annual emission rate of approximately 0.22 lb/MMBtu with LNB and
SOFA. This represents a 41.5 percent reduction from the baseline
emission rate of 0.37 lb/MMBtu.
The post-combustion control technologies, SNCR and SCR, have been
evaluated in combination with combustion controls. That is, the inlet
concentration to the post-combustion controls is assumed to be 0.22 lb/
MMBtu (annual). This allows the equipment and operating and maintenance
costs of the post-combustion controls to be minimized based on the
lower inlet NOX concentration.
Typically, SNCR reduces NOX an additional 20 to 30
percent above combustion controls without excessive NH3
slip.\211\ For this analysis, the control efficiency of SNCR has been
calculated based on the formula in the 2015 draft CCM SNCR
chapter,\212\ which for Huntington Unit 1 yields an additional
reduction of 21.7 percent after combustion controls. When combined with
LNB and SOFA, SNCR is anticipated to achieve an annual emission rate of
0.17 lb/MMBtu, corresponding to an overall control efficiency of 54.2
percent.
---------------------------------------------------------------------------
\211\ Institute of Clean Air Companies, White Paper, SNCR for
Controlling NOX Emissions, pp. 4, 9 (Feb. 2008).
\212\ See [DRAFT] 2015 SNCR CCM (July 2015), Figure 1.1c: SNCR
NOX Reduction Efficiency Versus Baseline NOX
Levels for Coal-fired Utility Boilers.
---------------------------------------------------------------------------
SCR can achieve performance emission rates as low as 0.04 to 0.07
lb/MMBtu on an annual basis.\213\ For this analysis, consistent with
our actions elsewhere, as well with PacifiCorp's analysis, we use an
annual emission rate of 0.05 lb/MMBtu for SCR, which when combined with
LNB and SOFA achieves an overall control efficiency of 86.7 percent.
---------------------------------------------------------------------------
\213\ Srivastava, R., Hall, R., Khan, S., Lani, B., & Culligan,
K., Nitrogen Oxides Emission Control Options for Coal-Fired Utility
Boilers, 55 J. Air & Waste Mgmt. Assoc. 1367, 1367-88 (2005).
---------------------------------------------------------------------------
A summary of emissions projections for the control options
evaluated is provided in Table 25.
Table 25--Summary of NOX BART Analysis Control Technologies for Huntington Unit 1
----------------------------------------------------------------------------------------------------------------
Control Annual Emissions Remaining
Control option effectiveness emission rate reduction emissions
(%) (lb/MMBtu) (tpy) (tpy)
----------------------------------------------------------------------------------------------------------------
LNB/SOFA +SCR................................... 86.7 0.05 5,092 784
LNB/SOFA +SNCR.................................. 54.2 0.17 3,185 2,692
LNB/SOFA........................................ 41.5 0.22 2,440 3,436
Baseline \1\.................................... .............. 0.37 .............. 5,876
----------------------------------------------------------------------------------------------------------------
\1\ Baseline emissions were determined by averaging the annual emissions from 2001 to 2003 as reported to EPA
Air Markets Program Data available at http://ampd.epa.gov/ampd/.
Step 4: Evaluate Impacts and Document Results
Part 1--Costs of Compliance
We obtained capital costs for LNB and SOFA from the 2014 PacifiCorp
BART analysis. PacifiCorp did not report any operating and maintenance
costs for LNB and SOFA. Similarly, we obtained capital cost estimates
for LNB and SOFA with SNCR from the 2014 PacifiCorp BART analysis.
However, for operating and maintenance costs we propose to rely on the
draft 2015 draft SNCR chapter of the CCM. Refer to the ATP report for
details. Capital costs for LNB and SOFA with SCR were also obtained
from the 2014 PacifiCorp BART analysis. However, PacifiCorp's capital
costs were adjusted to account for items that were double-counted or
should not be allowed under the CCM, such as AFUDC.\214\ In addition,
the capital costs were adjusted to account for a significant
overestimation of the catalyst volume and related costs. These
adjustments are documented in the ATP report and associated spread
sheet. A discussion of operating and maintenance costs of SCR is also
included in the ATP report. For the reasons given in the report, we
propose to adopt the cost estimates contained in it.
---------------------------------------------------------------------------
\214\ See 79 FR 5032, 5133 (Jan. 30, 2014) (discussing reasons
for rejecting use of AFUDC).
---------------------------------------------------------------------------
A summary of our proposed cost estimates for all control options is
presented in Table 26.
Table 26--Summary of NOX BART Costs on Huntington Unit 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Emissions Average Cost
Control option Total capital Indirect Direct annual Total annual reductions effectiveness
investment annual cost cost cost (tpy) ($/ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB/SOFA................................................ $8.1M $0.8M $0M $0.8M 2,440 $332
LNB/SOFA/SNCR........................................... 15.5M 1.5M 2.0M 3.5M 3,185 1,098
LNB/SOFA/SCR............................................ 107.8M 10.3M 2.5M 12.8M 5,092 2,515
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parts 2 and 3--Energy and Non-Air Quality Environmental Impacts of
Compliance
SNCR slightly reduces the thermal efficiency of a boiler as the
reduction reaction uses thermal energy from the boiler, decreasing the
energy available for power generation.\215\ Using the CCM, we have
calculated the electrical power consumption of SNCR to be 361,000 kW-hr
per year for Huntington Unit 1.
---------------------------------------------------------------------------
\215\ EPA Air Pollution Control Cost Manual, pp. 1-21 (6th ed.
2002).
---------------------------------------------------------------------------
For SCR, the thermal efficiency is much more reduced because the
new ductwork and the reactor's catalyst layers decrease the flue gas
pressure. As
[[Page 2043]]
a result, additional fan power is necessary to maintain the flue gas
flow rate through the ductwork and reactor. Using the CCM, we have
calculated the electrical power consumption of SCR to be approximately
18,617,000 kW-hr per year for Huntington Unit 1.
Both SCR and SNCR require some minimal electricity to service
pretreatment and injection equipment, pumps, compressors, and control
systems. The energy requirements described earlier are not significant
enough to warrant elimination of either SNCR or SCR as BART. In
addition, the cost of the additional energy requirements has been
included in our cost effectiveness calculations.
SNCR and SCR will slightly increase the quantity of ash that will
need to be disposed. In addition, transportation and storage of
chemical reagents may result in spills or releases. However, these non-
air quality environmental impacts do not warrant elimination of either
SNCR or SCR as BART.
There are no additional energy requirements associated with the new
LNB and SOFA, and no significant non-air quality environmental impacts.
In summary, we propose to determine that we have adequately
considered these impacts by including cost of additional energy in cost
effectiveness and assessing non-air quality environmental impacts as
insufficient to eliminate or weigh against any of the BART options.
Part 4--Remaining Useful Life
PacifiCorp assumes a remaining useful life of at least 20 years for
Huntington Unit 1 in its BART analysis, and has not indicated any
intention to retire, or curtail generation from, Huntington Unit 1.
Therefore, this factor does not preclude any of the control options
considered. In addition, this factor does not impact our BART
calculation of cost effectiveness because annualized costs have been
calculated over a 20 year period for each of the control options
considered. We propose that this gives adequate consideration to this
factor.
Step 5: Evaluate Visibility Impacts
Table 27 presents the highest of the 98th percentile visibility
improvements at the affected Class I areas for the three meteorological
years modeled, 2001 through 2003. Tables 28 and 29 present the number
of days (summed across three years) with impacts greater than the
contribution and causation thresholds--0.5 dv and 1.0 dv, respectively.
Table 27--Huntington Unit 1--Visibility Improvements
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA
Class I Area LNB with SOFA and SNCR and SCR
([Delta]dv) ([Delta]dv) ([Delta]dv)
----------------------------------------------------------------------------------------------------------------
Arches NP....................................................... 0.684 0.907 1.488
Black Canyon of the Gunnison NP................................. 0.156 0.205 0.328
Bryce Canyon NP................................................. 0.222 0.292 0.473
Canyonlands NP.................................................. 0.851 1.133 1.881
Capitol Reef NP................................................. 0.493 0.651 1.108
Flat Tops WA.................................................... 0.181 0.239 0.383
Grand Canyon NP................................................. 0.200 0.262 0.419
Mesa Verde NP................................................... 0.215 0.284 0.462
Zion NP......................................................... 0.150 0.198 0.320
----------------------------------------------------------------------------------------------------------------
Table 28--Huntington Unit 1--Days Greater Than 0.5 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA
Class I Area Baseline LNB with SOFA and SNCR LNB with SOFA
(days) (days) (days) and SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP....................................... 237 221 210 180
Black Canyon of the Gunnison NP................. 45 33 30 23
Bryce Canyon NP................................. 36 26 25 19
Canyonlands NP.................................. 277 249 244 210
Capitol Reef NP................................. 131 117 116 99
Flat Tops WA.................................... 64 41 37 27
Grand Canyon NP................................. 40 35 34 27
Mesa Verde NP................................... 63 46 41 30
Zion NP......................................... 21 16 16 14
----------------------------------------------------------------------------------------------------------------
Table 29--Huntington Unit 1--Days Greater than 1.0 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA
Class I Area Baseline LNB with SOFA and SNCR LNB with SOFA
(days) (days) (days) and SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP....................................... 146 121 117 86
Black Canyon of the Gunnison NP................. 16 7 7 3
Bryce Canyon NP................................. 19 13 9 5
Canyonlands NP.................................. 175 153 143 117
Capitol Reef NP................................. 91 74 69 55
[[Page 2044]]
Flat Tops WA.................................... 17 9 8 3
Grand Canyon NP................................. 19 13 12 9
Mesa Verde NP................................... 22 13 10 4
Zion NP......................................... 11 8 6 4
----------------------------------------------------------------------------------------------------------------
Select BART.
A summary of our impacts analysis for Huntington Unit 1 is
presented in Table 30.
Table 30--Summary of Huntington Unit 1 Impacts Analysis
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual Total Visibility impacts *
emission Emission annual Average cost Incremental cost -------------------------------------
Control option rate (lb/ reduction costs effectiveness effectiveness ($/ton) Improvement Days > Days >
MMBtu) (tpy) (million$) ($/ton) (dv) 0.5 dv 1.0 dv
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB with SOFA...................... 0.22 2,440 $0.8M $332 ...................... 0.851 249 153
LNB with SOFA and SNCR............. 0.17 3,185 3.5M 1,098 3,609................. 1.113 244 143
LNB with SOFA and SCR.............. 0.05 5,092 12.8M 2,515 $4,879 (compared to 1.881 210 117
LNB with SOFA and
SNCR).
$4,522 (compared to
LNB with SOFA).
--------------------------------------------------------------------------------------------------------------------------------------------------------
* At the most impacted Class I area, Canyonlands National Park.
In determining what to co-propose as BART, we have taken into
consideration all five of the statutory factors required by the CAA:
The costs of compliance, the energy and non-air quality environmental
impacts of compliance, any existing pollution control technology in use
at the source, the remaining useful life of the source, and the degree
of improvement in visibility which may reasonably be anticipated to
result from the use of such technology. Later on we provide a
justification for our selection of BART, including an explanation of
how each of the CAA factors was used in that selection.
As described in step 1 previously, we have considered the existing
pollution control technology in use at the source. We note that
Huntington Unit 1 was equipped with LNB and SOFA in the fall of 2010 in
order to meet state-law requirements in the 2011 Utah RH SIP submittal,
which we did not approve. In this co-proposal we have to evaluate
control technologies and baseline emissions from the correct starting
point, that is, prior to the installation of the combustion controls
pursuant to state-law NOX limitations.\216\ As a result, we
used the period 2001-2003 as the appropriate period for baseline
emissions, in order to provide a realistic depiction of annual
emissions for Huntington Unit 1 prior to installation of combustion
controls.
---------------------------------------------------------------------------
\216\ See 79 FR 5032, 5105-1 (Jan. 30, 2012).
---------------------------------------------------------------------------
We have considered the energy and non-air quality environmental
impacts of compliance and propose to find that they do not appreciably
favor one control option over another, or preclude a particular control
option from selection. And finally, we have considered the remaining
useful life of the source and find that it is sufficiently long
(greater than 20 years) so as not to favor or preclude any of the
control options. As a result, the remaining factors--the costs of
compliance and visibility improvement--are the primary factors that
lead us to our proposed BART selection for Huntington Unit 1.
Having already considered the other factors, in order to select
BART we propose to weigh the costs of compliance against visibility
impacts by generally comparing them with BART determinations that have
been made elsewhere. Specifically, we propose to compare the average
cost-effectiveness, incremental cost-effectiveness, visibility
improvement, and incremental visibility improvement for LNB and SOFA
with SCR with BART determinations where the EPA and States have based
their determination on the same metrics. The most comparable
determinations are the same as for Hunter Unit 1. The most comparable
determination appears to be in EPA's final action for Wyoming's
regional haze SIP, in which EPA promulgated a FIP for three units at
Laramie River Station and determined BART to be LNB and SOFA with SCR
for the three units.\217\ On a per-unit basis, the visibility
improvement from that control option was 0.52 to 0.57 dv, and across
all three units the sum of the improvement was 1.62 dv. The average
cost-effectiveness ranged from $4,375/ton to $4,461/ton, while the
incremental cost-effectiveness ranged from $5,449 to $5,871/ton.
Finally, the incremental visibility improvement as compared to LNB and
SOFA with SNCR was significant. On the other hand, at Dave Johnston
Units 3 and 4 (for example), where EPA rejected LNB and SOFA with SCR,
the incremental cost-effectiveness value of LNB and SOFA with SCR was
much higher and incremental visibility benefit lower than at Laramie
River Station.\218\
---------------------------------------------------------------------------
\217\ 79 FR 5032, 5047 (Jan. 30, 2014).
\218\ 79 FR 5032, 5049.
---------------------------------------------------------------------------
[[Page 2045]]
There are other BART determinations in which SCR has been selected
as BART (either alone or in conjunction with LNB and SOFA) based on
similar metrics, although those determinations may not have explicitly
discussed incremental cost-effectiveness and incremental visibility
benefits on a per-unit basis. First, the State of Colorado selected,
and the EPA approved, SCR as NOX BART for Public Service
Company's Hayden Station, Units 1 and 2.\219\ Hayden Units 1 and 2 were
equipped with first generation LNB and over-fire air (OFA) installed in
1999.\220\ In its BART determination, Colorado considered these
existing controls as given and analyzed as feasible controls upgraded
LNB, SNCR, and SCR. Based on an average cost-effectiveness of $3,385/
ton and $4,064/ton, incremental cost-effectiveness (as compared with
LNB and OFA with SNCR) of $5,326/ton and $7,331/ton, and visibility
improvement of 1.12 dv and 0.85 dv at the most impacted Class I area,
respectively, Colorado selected SCR as BART for Units 1 and 2. In this
case, due to the existing controls at Hayden Station, the cost-
effectiveness values for SCR for Hayden Units 1 and 2 should be
compared to the incremental cost-effectiveness values (as compared with
LNB and SOFA, and with LNB and SOFA with SNCR) for SCR for Huntington
Unit 1, and similarly for incremental visibility benefits. We think
they are comparable, particularly for Hayden Unit 2, and considering
that Huntington Unit 1 significantly impacts several Class I areas,
while Colorado selected SCR for Hayden based solely on the visibility
improvement at the most impacted Class I area, Mt. Zirkel Wilderness.
---------------------------------------------------------------------------
\219\ 77 FR 18069 (Mar. 26, 2012) (proposal); 77 FR 76871 (Dec.
31, 2012) (final).
\220\ Colorado Department of Health and Environment, Air
Pollution Control Division, Best Available Retrofit Technology
(BART) Analysis of Control Options For Public Service Company--
Hayden Station, p. 5, available at https://www.colorado.gov/pacific/sites/default/files/AP_PO_Hayden-Power-Plant_0.pdf.
---------------------------------------------------------------------------
Another comparable determination can be found in EPA's FIP for
Arizona Public Service's Cholla Power Plant, Units 2, 3, and 4, in
which EPA determined that NOX BART was SCR.\221\ Similarly
to Colorado's determination for Hayden, EPA considered the existing
controls, LNB and OFA, at the three units and estimated average cost-
effectiveness values for SCR of $3,114/ton, $3,472/ton, and $3,395/ton,
and incremental cost-effectiveness values (as compared to LNB and OFA
with SNCR) of $3,257/ton, $3,811/ton, and $3,661/ton, respectively, for
Units 2, 3, and 4. EPA's modeling showed a source-wide visibility
improvement for SCR of 1.34 dv at the most impacted Class I area. Based
on these metrics, EPA determined NOX BART to be SCR for the
three units. In this case, as with Hayden, the average cost-
effectiveness of SCR at Cholla should be compared with the incremental
cost-effectiveness of SCR (as compared with just LNB and SOFA) at
Huntington Unit 1. The cost-effectiveness values for Huntington Unit 1
are somewhat higher than at Cholla, but on the other hand the source-
wide visibility improvement at Huntington Units 1 and 2 (as obtained by
summing the per-unit improvements from Units 1 and 2) \222\ from LNB
and SOFA with SCR is 2.759 dv at the most impacted Class I area, with
incremental visibility improvements of 1.29 dv and 0.932 dv over LNB
and SOFA and LNB and SOFA with SNCR, respectively. These visibility
improvements are very much in line with those at Cholla, and given that
the incremental cost-effectiveness of SCR at Huntington Unit 1 is still
reasonable, the comparison with Cholla also supports selection of SCR
for Huntington Unit 1. We invite comment on other potentially relevant
BART determinations and our methodology generally.
---------------------------------------------------------------------------
\221\ 77 FR 42834 (July 20, 2012) (proposal); 77 FR 72512,
72514-15 (Dec. 5, 2012) (final).
\222\ We use the source-wide number here to compare with the
Cholla determination; in addition as explained above we must
consider source-wide visibility improvements.
---------------------------------------------------------------------------
Based on these comparisons, we think LNB and SOFA with SCR is very
cost-effective at $2,515/ton, and provides substantial visibility
benefits at several Class I areas. For example, the visibility
improvement from that control option is 1.488 dv at Arches NP, 1.881 dv
at Canyonlands NP, and 1.108 dv at Capitol Reef NP. The incremental
cost-effectiveness of SCR, $4,879/ton, is by comparison with the
Laramie River Station BART determination also reasonable. This
comparison also shows that costs are justified in light of the
substantial visibility benefits, both total and incremental.
In the case of Huntington, the unit level visibility improvements
justify the most stringent level of control, SCR, for each of the two
Huntington units. Necessarily, when we consider the source-wide
visibility improvements, they will be larger and also justify the most
stringent level of control.
Accordingly, for Huntington Unit 1, we propose to find that BART
for NOX is LNB and SOFA with SCR, represented by an emission
limit of 0.07 lb/MMBtu (30-day rolling average). The proposed BART
emission limit of 0.07 lb/MMBtu allows for a sufficient margin of
compliance for a 30-day rolling average limit that would apply at all
times, including startup, shutdown, and malfunction.\223\ We are also
proposing monitoring, recordkeeping, and reporting requirements as
described in our proposed regulatory text for 40 CFR 52.2336.
---------------------------------------------------------------------------
\223\ Emission limits such as BART are required to be met on a
continuous basis. See 70 FR 39104, 39172 (July 6, 2005) (stating
that emissions limits including BART are to be met on a ``continuous
basis'' in the BART Guidelines, section V); 42 U.S.C. 7602(k)
(noting that emission limits are to be on ``a continuous basis'').
---------------------------------------------------------------------------
Under 40 CFR 51.308(e)(1)(iv), ``each source subject to BART [is]
required to install and operate BART as expeditiously as practicable,
but in no event later than 5 years after approval of the implementation
plan revision.'' In light of the considerable effort involved to
retrofit SCR, we propose that five years is as expeditiously as
practicable. Therefore, we propose a compliance deadline of five years
from the date our final FIP becomes effective.
b. Huntington Unit 2
Generally, Huntington Unit 2 is identical to Unit 1. The Huntington
Unit 2 boiler is of tangential-fired design with newer generation low-
NOX burners and separated overfire air which were installed
in winter 2006. Huntington Unit 2 currently achieves an annual emission
rate of approximately 0.21 lb/MMBtu with these combustion controls.
Under Utah's submitted regional haze SIP, Unit 2 is subject to a state-
law NOX emission limit of 0.26 lb/MMBtu on a 30-day rolling
average. Prior to the installation of LNB and SOFA the unit operated
with an actual annual emission rate of about 0.39 lb/MMBtu.
Step 1: Identify All Available NOX Control Technologies
For the same reasons as for Huntington Unit 1, we propose to adopt
the identification of available NOX control technologies in
PacifiCorp's 2012 BART analysis to satisfy Step 1, and we refer the
reader to the 2012 PacifiCorp BART analysis for details on the
available NOX control technologies.
Step 2: Eliminate Technically Infeasible Options
In its 2012 BART analysis,\224\ PacifiCorp eliminated available
NOX control technologies that PacifiCorp evaluated as
technologically infeasible for Huntington Unit 2. The remaining
technologically feasible control technologies are the combustion
[[Page 2046]]
controls, LNB and SOFA, and the post-combustion controls, SNCR and SCR.
---------------------------------------------------------------------------
\224\ PacifiCorp BART Analysis for Huntington Unit 2, pp. 2.a-
106--2.a-124 (2012).
---------------------------------------------------------------------------
We agree with PacifiCorp's evaluation of technologically available
controls for Huntington Unit 2 and propose to adopt it for Step 2.
Step 3: Evaluate Control Effectiveness of Remaining Control
Technologies
As noted previously, Huntington Unit 2 is currently achieving an
actual annual emission rate of approximately 0.21 lb/MMBtu with LNB and
SOFA. This represents a 44.6 percent reduction from the baseline
emission rate of 0.39 lb/MMBtu.
The post-combustion control technologies, SNCR and SCR, have been
evaluated in combination with combustion controls. That is, the inlet
concentration to the post-combustion controls is assumed to be 0.21 lb/
MMBtu (annual). This allows the equipment and operating and maintenance
costs of the post-combustion controls to be minimized based on the
lower inlet NOX concentration.
Typically, SNCR reduces NOX an additional 20 to 30
percent above combustion controls without excessive NH3
slip.\225\ For this analysis, the control efficiency of SNCR has been
calculated based on the formula in the 2015 draft CCM SNCR
chapter,\226\ which for Huntington Unit 2 yields an additional
reduction of 21.5 percent after combustion controls. When combined with
LNB and SOFA, SNCR is anticipated to achieve an annual emission rate of
0.17 lb/MMBtu, corresponding to an overall control efficiency of 56.6
percent.
---------------------------------------------------------------------------
\225\ Institute of Clean Air Companies, White Paper, SNCR for
Controlling NOX Emissions, pp. 4 and 9 (Feb. 2008).
\226\ EPA Selective Noncatalytic, Reduction Cost Manual Draft
for Public Comment, p. 1-6 (Figure 1.1c: SNCR NOX
Reduction Efficiency Versus Baseline NOX Levels for Coal-
fired Utility Boilers) (June 5, 2015).
---------------------------------------------------------------------------
SCR can achieve performance emission rates as low as 0.04 to 0.07
lb/MMBtu on an annual basis.\227\ For this analysis, consistent with
our actions elsewhere, as well with PacifiCorp's analysis, we use an
annual emission rate of 0.05 lb/MMBtu for SCR, which when combined with
LNB and SOFA achieves an overall control efficiency of 87.0 percent.
---------------------------------------------------------------------------
\227\ Srivastava, R., Hall, R., Khan, S., Lani, B., & Culligan,
K., Nitrogen Oxides Emission Control Options for Coal-Fired Utility
Boilers, 55 J. Air & Waste Mgmt Assoc. 55, 1367, 1367-88 (2005).
---------------------------------------------------------------------------
A summary of emissions projections for the control options
evaluated is provided in Table 31.
Table 31--Summary of NOX BART Analysis Control Technologies for Huntington Unit 2
----------------------------------------------------------------------------------------------------------------
Control Annual Emissions Remaining
Control option effectiveness emission rate reduction emissions
(%) (lb/MMBtu) (tpy) (tpy)
----------------------------------------------------------------------------------------------------------------
LNB/SOFA +SCR................................... 87.0 0.05 5,023 747
LNB/SOFA +SNCR.................................. 56.6 0.17 3,264 2,506
LNB/SOFA........................................ 44.6 0.21 2,576 3,194
Baseline\1\..................................... -- 0.39 -- 5,770
----------------------------------------------------------------------------------------------------------------
\1\ Baseline emissions were determined by averaging the annual emissions from 2001 to 2003 as reported to EPA
Air Markets Program Data available at http://ampd.epa.gov/ampd/.
Step 4: Evaluate Impacts and Document Results
Part 1--Costs of Compliance
We obtained capital costs for LNB and SOFA from the 2014 PacifiCorp
BART analysis. PacifiCorp did not report any operating and maintenance
costs for LNB and SOFA. Similarly, we obtained capital cost estimates
for LNB and SOFA with SNCR from the 2014 PacifiCorp BART analysis.
However, for operating and maintenance costs we propose to rely on the
draft 2015 draft SNCR chapter of the CCM. Refer to the ATP report for
details. Capital costs for LNB and SOFA with SCR were also obtained
from the 2014 PacifiCorp BART analysis. However, PacifiCorp's capital
costs were adjusted to account for items that were double-counted or
should not be allowed under the CCM, such as AFUDC.\228\ In addition,
the capital costs were adjusted to account for a significant
overestimation of the catalyst volume and related costs. These
adjustments are documented in the ATP report and associated spread
sheet. A discussion of operating and maintenance costs of SCR is also
included in the ATP report. For the reasons given in the report, we
propose to adopt the cost estimates contained in it.
---------------------------------------------------------------------------
\228\ See 79 FR 5032, 5133 (discussing reasons for rejecting use
of AFUDC).
---------------------------------------------------------------------------
A summary of our proposed cost estimates for all control options is
presented in Table 32.
Table 32--Summary of NOX BART Costs on Huntington Unit 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Emissions Average cost
Control option Total capital Indirect Direct annual Total annual reductions effectiveness
investment annual costs costs cost (tpy) ($/ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB/SOFA................................................ $9.4M $0.9M $0M $0.9M 2,576 $365
LNB/SOFA/SNCR........................................... 16.7M 1.6M 1.9M 3.5M 3,264 1,075
LNB/SOFA/SCR............................................ 109.4M 10.4M 2.4M 12.9M 5,023 2,563
--------------------------------------------------------------------------------------------------------------------------------------------------------
Parts 2 and 3--Energy and Non-Air Quality Environmental Impacts of
Compliance
The energy and non-air quality impacts for Huntington Unit 2 are
nearly identical to those for Huntington Unit 1 as discussed
previously. Accordingly, for the same reasons as for Huntington Unit 1,
we propose to determine that we have adequately considered these
impacts by including cost of additional energy in cost effectiveness
and assessing non-air quality environmental impacts as insufficient to
eliminate or weigh against any of the BART options.
[[Page 2047]]
Part 4--Remaining Useful Life
PacifiCorp assumes a remaining useful life of at least 20 years for
Huntington Unit 2 in its BART analysis, and has not indicated any
intention to retire, or curtail generation from, Huntington Unit 2.
Therefore, this factor does not preclude any of the control options
considered. In addition, this factor does not impact our BART
calculation of cost effectiveness because annualized costs have been
calculated over a 20 year period for each of the control options
considered. We propose that this gives adequate consideration to this
factor.
Step 5: Evaluate Visibility Impacts
Table 33 presents the highest of the 98th percentile visibility
improvements at the affected Class I areas for the three meteorological
years modeled, 2001 through 2003. Tables 34 and 35 present the number
of days (summed across three years) with impacts greater than the
contribution and causation thresholds--0.5 dv and 1.0 dv, respectively.
Table 33--Huntington Unit 2--Visibility Improvements
----------------------------------------------------------------------------------------------------------------
LNB with SOFA LNB with SOFA
Class I Area LNB with SOFA and SNCR and SCR
([Delta]dv) ([Delta]dv) ([Delta]dv)
----------------------------------------------------------------------------------------------------------------
Arches NP....................................................... 0.625 0.816 1.316
Black Canyon of the Gunnison NP................................. 0.143 0.184 0.292
Bryce Canyon NP................................................. 0.205 0.266 0.424
Canyonlands NP.................................................. 0.776 1.016 1.657
Capitol Reef NP................................................. 0.449 0.584 0.955
Flat Tops WA.................................................... 0.168 0.217 0.343
Grand Canyon NP................................................. 0.183 0.236 0.371
Mesa Verde NP................................................... 0.199 0.258 0.414
Zion NP......................................................... 0.136 0.176 0.281
----------------------------------------------------------------------------------------------------------------
Table 34--Huntington Unit 2--Days Greater Than 0.5 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA
Class I Area Baseline LNB with SOFA and SNCR LNB with SOFA
(days) (days) (days) and SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP....................................... 237 223 214 186
Black Canyon of the Gunnison NP................. 45 35 32 26
Bryce Canyon NP................................. 36 26 26 23
Canyonlands NP.................................. 277 254 244 220
Capitol Reef NP................................. 131 119 116 104
Flat Tops WA.................................... 64 44 39 31
Grand Canyon NP................................. 40 36 35 30
Mesa Verde NP................................... 63 48 43 31
Zion NP......................................... 21 17 16 15
----------------------------------------------------------------------------------------------------------------
Table 35--Huntington Unit 2--Days Greater Than 1.0 Deciview
[Three year total]
----------------------------------------------------------------------------------------------------------------
LNB with SOFA
Class I Area Baseline LNB with SOFA and SNCR LNB with SOFA
(days) (days) (days) and SCR (days)
----------------------------------------------------------------------------------------------------------------
Arches NP....................................... 146 122 118 98
Black Canyon of the Gunnison NP................. 16 8 7 4
Bryce Canyon NP................................. 19 15 13 6
Canyonlands NP.................................. 175 153 149 126
Capitol Reef NP................................. 91 75 70 59
Flat Tops WA.................................... 17 9 8 4
Grand Canyon NP................................. 19 13 13 9
Mesa Verde NP................................... 22 13 13 6
Zion NP......................................... 11 8 6 4
----------------------------------------------------------------------------------------------------------------
Select BART.
A summary of our impacts analysis for Huntington Unit 2 is
presented in Table 36.
[[Page 2048]]
Table 36--Summary of Huntington Unit 2 Impacts Analysis
--------------------------------------------------------------------------------------------------------------------------------------------------------
Annual Visibility impacts *
emission Emission Total Average cost Incremental cost -----------------------------------------
Control option rate (lb/ reduction annual effectiveness effectiveness ($/ Improvement Days >0.5 Days >1.0
MMBtu) (tpy) costs ($) ($/ton) ton) (dv) dv dv
--------------------------------------------------------------------------------------------------------------------------------------------------------
LNB with SOFA.................... 0.21 2,576 $0.9M $365 .................... 0.776 254 153
LNB with SOFA and SNCR........... 0.17 3,264 3.5M 1,075 $3,730.............. 1.016 244 149
LNB with SOFA and SCR............ 0.05 5,023 12.9M 2,563 $5,326.............. 1.657 220 126
(compared to LNB
with SOFA and SNCR).
$4,877 (compared to
LNB with SOFA).
--------------------------------------------------------------------------------------------------------------------------------------------------------
* At the most impacted Class I area, Canyonlands National Park.
In determining what to co-propose as BART, we have taken into
consideration all five of the statutory factors required by the CAA:
The costs of compliance, the energy and non-air quality environmental
impacts of compliance, any existing pollution control technology in use
at the source, the remaining useful life of the source, and the degree
of improvement in visibility which may reasonably be anticipated to
result from the use of such technology. Later on we provide a
justification for our selection of BART, including an explanation of
how each of the CAA factors was used in that selection.
We have considered the energy and non-air quality environmental
impacts of compliance and propose to find that they do not appreciably
favor one control option over another, or preclude a particular control
option from selection. The existing pollution controls have been
accounted for in our evaluation of BART, and also would not favor or
preclude any of the control options considered. And finally, we have
considered the remaining useful life of the source and find that it is
sufficiently long (greater than 20 years) so as not to favor or
preclude any of the control options. As a result, the remaining
factors--the costs of compliance and visibility improvement--are the
primary factors that lead us to our proposed BART selection for
Huntington Unit 2.
In order to select BART we propose to weigh the costs of compliance
against visibility impacts by generally comparing them with BART
determinations that have been made elsewhere. Specifically, we propose
to compare the average cost-effectiveness, incremental cost-
effectiveness, visibility improvement, and incremental visibility
improvement for LNB and SOFA with SCR with BART determinations where
the EPA and States have based their determination on the same metrics.
The most comparable determinations are the same as for Huntington Unit
1: The Laramie River Station, Hayden Station, and Cholla Power Plant
determinations.
Based on these comparisons, we think LNB and SOFA with SCR is very
cost-effective at $2,563/ton, and provides substantial visibility
benefits at several Class I areas. For example, the visibility
improvement from that control option is 1.316 at Arches NP and 1.657 dv
Canyonlands NP. The incremental cost-effectiveness of SCR, $5,326/ton,
is by comparison also reasonable. This comparison also shows that costs
are justified in light of the substantial visibility benefits, both
total and incremental.
In the case of Huntington, the unit level visibility improvements
justify the most stringent level of control, SCR, for each of the two
Huntington units. Necessarily, when we consider the source-wide
visibility improvements, they will be larger and also justify the most
stringent level of control. In addition, the unit level visibility
improvements and source-wide visibility improvements at other impacted
Class I areas, particularly Arches NP and Capitol Reef NP, support the
most stringent level of control.
Accordingly, for Huntington Unit 2, we propose to find that BART
for NOX is LNB and SOFA with SCR, represented by an emission
limit of 0.07 lb/MMBtu (30-day rolling average). The proposed BART
emission limit of 0.07 lb/MMBtu allows for a sufficient margin of
compliance for a 30-day rolling average limit that would apply at all
times, including startup, shutdown, and malfunction.\229\ We are also
proposing monitoring, recordkeeping, and reporting requirements as
described in our proposed regulatory text for 40 CFR 52.2336.
---------------------------------------------------------------------------
\229\ Emission limits such as BART are required to be met on a
continuous basis. See 70 FR 39104, 39172 (July 6, 2005) (stating
that emissions limits including BART are to be met on a ``continuous
basis'' in the BART Guidelines, section V); 42 U.S.C. 7602(k)
(noting that emission limits are to be on ``a continuous basis'').
---------------------------------------------------------------------------
Under Sec. 51.308(e)(1)(iv), ``each source subject to BART [is]
required to install and operate BART as expeditiously as practicable,
but in no event later than 5 years after approval of the implementation
plan revision.'' In light of the considerable effort involved to
retrofit SCR, we propose that five years is as expeditiously as
practicable. Therefore, we propose a compliance deadline of five years
from the date our final FIP becomes effective.
4. Federal Monitoring, Recordkeeping, and Reporting
We have explained earlier in section III.C.4 that the CAA and 40
CFR part 51, subpart K require that SIPs, including the regional haze
SIP, contain certain elements sufficient to ensure emission limits are
practically enforceable. EPA is proposing to disapprove Utah's
NOX BART Alternative along with the associated monitoring,
recordkeeping and reporting requirements in SIP sections IX.H.21 and
H.22. EPA is proposing regulatory language as part of our FIP that
specifies monitoring, recordkeeping, and reporting requirements for all
BART sources. For purposes of consistency, EPA is proposing to adopt
language that is the same as we have adopted for other states in Region
8.
E. PM10 BART Determinations
As discussed earlier in section IV.B.2, Utah determined that the
PM10 BART emission limit for Hunter Units 1 and 2 and
Huntington Units 1 and 2 was 0.015 lb/MMBtu based on a three-run test
average. Utah noted that because the most stringent technology is in
place at
[[Page 2049]]
these units and that the PM10 emission limits have been made
enforceable in the SIP, no further analysis was required.
EPA has reviewed Utah's PM10 BART streamlined five-
factor analysis and PM10 BART determinations for Hunter
Units 1 and 2 and Huntington Units 1 and 2 and proposes to find that
these determinations meet the requirements of 40 CFR 51.309(d)(4)(vii).
The fabric filter baghouses installed at these BART units are
considered the most stringent technology available. The emission limit
of 0.015 lb/MMBtu at these units represents the most stringent emission
limit for PM10 and is within the range of PM10
BART limits that EPA has approved in other states.\230\ Utah's use of a
streamlined approach to the five-factor analysis is reasonable as the
BART Guidelines provide that a comprehensive BART analysis can be
avoided if a source commits to a BART determination that consists of
the most stringent controls available.\231\
---------------------------------------------------------------------------
\230\ For example, Wyoming, Naughton Unit 3, Jim Bridger Units 1
through 4, Dave Johnston Units 3 and 4, and Wyodak Unit 1. See 40
CFR 52.2636; 79 FR 5220, (Jan. 30, 2014).
\231\ 40 CFR 51, appendix Y, section IV.D.1.9.
---------------------------------------------------------------------------
Utah's regulatory text provides, ``[e]missions of particulate (PM)
shall not exceed 0.015 lb/MMBtu heat input from each boiler based on a
3-run test average.'' \232\ It further states that ``[s]tack testing
for the emission limitation shall be performed each year on each
boiler.'' \233\ We note that BART limits must apply at all times.\234\
Furthermore, EPA's credible evidence rule requires that a state's plan
must not preclude the use of any credible evidence or information,
which can include evidence and information other than the test method
specified in the plan, that would indicate whether a source was in
compliance with applicable requirements.\235\
---------------------------------------------------------------------------
\232\ Utah Regional Haze State Implementation Plan: Emission
Limits & Operating Practices, Sections IX.H.22.a.i.A-B,
IX.H.22.b.i.A-B (2015).
\233\ Id.
\234\ See 42 U.S.C. 7602(k); 40 CFR part 51, appendix Y, section
V.
\235\ 40 CFR 51.212(c).
---------------------------------------------------------------------------
Consistent with these requirements, we propose to interpret Utah's
regulatory text as imposing a PM10 limit of 0.015 lb/MMBtu
that applies at all times and does not preclude the use, including the
exclusive use, of any credible evidence or information, relevant to
whether a source is in compliance with the limit.
F. Consultation With FLMs
As discussed previously in section IV.G, Utah conducted FLM
consultation during late 2014, providing over 60 days prior to the
December 1, 2014 public hearing. Subsequently, the National Park
Service provided extensive comments in response to a second public
comment period in April 2015. Based on these considerations, we propose
to find that Utah has met the requirements of 40 CFR 308(i)(2).
VII. EPA's Proposed Actions
EPA is proceeding with co-proposals on Utah's June 3, 2015 and
October 20, 2015 regional haze SIP revisions. Later on is a summary of
our proposed actions. As noted above, EPA intends to finalize only one
proposal, although it may differ from what is presented here based on
any comments and additional information we receive.
A. Proposed Approval
We are proposing to approve the regional haze SIP revisions
submitted by the State of Utah on June 3, 2015 and October 20, 2015:
1. We are proposing to approve these aspects of the State's June 4,
2015, which rely on elements from prior approvals \236\:
---------------------------------------------------------------------------
\236\ As necessary for our proposed approval, we propose to fill
gaps in the 2015 Utah RH SIP submittals with the following already-
approved sections from the 2011 Utah RH SIP: Section XX.B.8, Figures
1 and 2, Affected Class I Areas, pp. 8-9; Section XX.D.6.b, Table 3,
BART-Eligible Sources in Utah, p. 21; Section. XX.D.6.c, Sources
Subject to BART, pp. 21-23.
---------------------------------------------------------------------------
NOX BART Alternative that includes
NOX, and SO2, emission reductions from Hunter
Units 1 through 3, Huntington 1 and 2, and Carbon Units 1 and 2, and
PM10 emission reductions from Carbon Units 1 and 2.
BART determinations and emission limits for
PM10 at Hunter Units 1 and 2 and Huntington Units 1 and 2.
Monitoring, recordkeeping and reporting requirements for
units subject to the BART Alternative and the PM10 emission
limits, including conditional approval of the recordkeeping
requirements for the PM10 emission limits.
2. We are proposing to approve these elements of the State's
October 20, 2015 SIP submittal:
Enforceable commitments to revise, at a minimum, SIP
Section XX.D.3.c and State rule R307-150 by March 2018 to clarify
emission inventory requirements for tracking compliance with the
SO2 milestone and properly accounting for the SO2
emission reductions due to the closure of the Carbon plant.
B. Proposed Partial Disapproval/Approval and Federal Implementation
Plan
1. We are proposing to approve these elements of the State's SIP
submittals, which rely on elements from prior approvals:\237\
---------------------------------------------------------------------------
\237\ Id.
---------------------------------------------------------------------------
BART determinations and emission limits for
PM10 at Hunter Units 1 and 2 and Huntington Units 1 and 2.
Monitoring, recordkeeping, and reporting requirements for
units subject to the PM10 emission limits, including
conditional approval of the recordkeeping requirements for the
PM10 emission limits.
2. We are proposing to disapprove these aspects of the State's June
4, 2015 SIP:
NOX BART Alternative that includes
NOX, and SO2, emission reductions from Hunter
Units 1 through 3, Huntington 1 and 2, and Carbon Units 1 and 2, and
PM10 emission reductions from Carbon Units 1 and 2.
Monitoring, recordkeeping and reporting requirements for
units subject to the BART Alternative.
The enforceable commitments to revise, at a minimum, SIP
Section XX.D.3.c and State rule R307-150 by March 2018.
3. We are proposing that if we finalize our co-proposal to
disapprove the NOX BART Alternative, we will promulgate a
FIP to address the deficiencies in the Utah regional haze SIPs. The
proposed FIP includes the following elements:
NOX BART determinations and limits for Hunter
Units 1 and 2, Huntington Units 1 and 2.
Monitoring, recordkeeping, and reporting requirements
applicable to Hunter Units 1 and 2, and Huntington Units 1 and 2.
VIII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review
This action is not a ``significant regulatory action'' under the
terms of Executive Order 12866 \238\ and was therefore not submitted to
the Office of Management and Budget (OMB) for review. This proposed
rule applies to only two facilities containing four BART units. It is
therefore not a rule of general applicability.
---------------------------------------------------------------------------
\238\ 58 FR 51735, 51738 (Oct. 4, 1993).
---------------------------------------------------------------------------
B. Paperwork Reduction Act
This proposed action does not impose an information collection
burden under the provisions of the Paperwork Reduction Act (PRA).\239\
Because this proposed rule applies to just two facilities, the PRA does
not apply.
---------------------------------------------------------------------------
\239\ 44 U.S.C. 3501 et seq.
---------------------------------------------------------------------------
[[Page 2050]]
C. Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
For purposes of assessing the impacts of this proposed rule on
small entities, small entity is defined as: (1) A small business as
defined by the Small Business Administration's (SBA) regulations at 13
CFR 121.201; (2) a small governmental jurisdiction that is a government
of a city, county, town, school district or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise which is independently owned and operated
and is not dominant in its field.
After considering the economic impacts of this proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities under the
RFA. This rule does not impose any requirements or create impacts on
small entities as small entities are not subject to the requirements of
this rule. Under the full approval approach in this proposed rule, EPA
would approve all elements of the State's submittals as meeting the
federal regional haze requirements and therefore EPA's action does not
impose any requirements.\240\ Under the partial approval approach, EPA
would disapprove the state's SIP submittal and promulgate a FIP that
consists of imposing federal controls to meet the BART requirement for
emissions on four specific BART units at two facilities in Utah. The
net result of this action is that EPA is proposing direct emission
controls on selected units at only two sources, and those sources are
large electric generating plants that are not owned by small entities,
and therefore the owners are not a small entities under the RFA.
---------------------------------------------------------------------------
\240\ See, e.g., Mid-Tex Elec. Coop., Inc. v. FERC, 773 F.2d 327
(D.C. Cir. 1985) (hereinafter Mid-Tex).
---------------------------------------------------------------------------
D. Unfunded Mandates Reform Act (UMRA)
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for federal agencies to assess the
effects of their regulatory actions on State, local, and Tribal
governments and the private sector. Under section 202 of UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for final rules with ``Federal mandates'' that may result in
expenditures to State, local, and Tribal governments, in the aggregate,
or to the private sector, of $100 million or more (adjusted for
inflation) in any one year. Before promulgating an EPA rule for which a
written statement is needed, section 205 of UMRA generally requires EPA
to identify and consider a reasonable number of regulatory alternatives
and adopt the least costly, most cost-effective, or least burdensome
alternative that achieves the objectives of the rule. The provisions of
section 205 of UMRA do not apply when they are inconsistent with
applicable law. Moreover, section 205 of UMRA allows EPA to adopt an
alternative other than the least costly, most cost-effective, or least
burdensome alternative if the Administrator publishes with the final
rule an explanation why that alternative was not adopted. Before EPA
establishes any regulatory requirements that may significantly or
uniquely affect small governments, including Tribal governments, it
must have developed under section 203 of UMRA a small government agency
plan. The plan must provide for notifying potentially affected small
governments, enabling officials of affected small governments to have
meaningful and timely input in the development of EPA regulatory
actions with significant federal intergovernmental mandates, and
informing, educating, and advising small governments on compliance with
the regulatory requirements.
Under Title II of UMRA, EPA has determined that this proposed rule
does not contain a federal mandate that may result in expenditures that
exceed the inflation-adjusted UMRA threshold of $100 million \241\ by
State, local, or Tribal governments or the private sector in any one
year. The private sector expenditures that would result from the
approach to promulgate a FIP would include BART controls for all four
units at the Hunter and Huntington plants would be $51.5 million \242\
per year. Additionally, we do not foresee significant costs (if any)
for state and local governments. Thus, because the annual expenditures
associated with the approach to promulgate a FIP are less than the
threshold of $100 million in any one year, this proposed rule is not
subject to the requirements of sections 202 or 205 of UMRA. This
proposed rule is also not subject to the requirements of section 203 of
UMRA because it contains no regulatory requirements that might
significantly or uniquely affect small governments.
---------------------------------------------------------------------------
\241\ Adjusted to 2014 dollars, the UMRA threshold becomes $152
million.
\242\ Andover Technology Partners, Cost of NOX BART
Controls on Utah EGUs, to EC/R, Inc. (Oct. 22, 2015).Andover
Technology Partners is a subcontractor to EC/R Incorporated.
---------------------------------------------------------------------------
E. Executive Order 13132: Federalism
Executive Order 13132, Federalism,\243\ revokes and replaces
Executive Orders 12612 (Federalism) and 12875 (Enhancing the
Intergovernmental Partnership). Executive Order 13132 requires EPA to
develop an accountable process to ensure ``meaningful and timely input
by State and local officials in the development of regulatory policies
that have federalism implications.'' \244\ ``Policies that have
federalism implications'' is defined in the Executive Order to include
regulations that have ``substantial direct effects on the States, on
the relationship between the national government and the States, or on
the distribution of power and responsibilities among the various levels
of government.'' \245\ Under Executive Order 13132, EPA may not issue a
regulation ``that has federalism implications, that imposes substantial
direct compliance costs, . . . and that is not required by statute,
unless [the federal government provides the] funds necessary to pay the
direct [compliance] costs incurred by the State and local
governments,'' or EPA consults with state and local officials early in
the process of developing the final regulation.\246\ EPA also may not
issue a regulation that has federalism implications and that preempts
state law unless the Agency consults with state and local officials
early in the process of developing the final regulation.
---------------------------------------------------------------------------
\243\ 64 FR 43255, 43255-43257 (Aug. 10, 1999).
\244\ 64 FR 43255, 43257.
\245\ Id.
\246\ Id.
---------------------------------------------------------------------------
This action does not have federalism implications. Neither of the
two approaches presented in this proposed rule will have substantial
direct effects on the states, on the relationship between the national
government and the states, or on the distribution of power and
responsibilities among the various levels of government, as specified
in Executive Order 13132. Under the full approval approach, this
proposed action would merely approve the state SIP as federally
enforceable. Under the partial approval approach, this proposed action
would merely address the State not fully meeting its
[[Page 2051]]
obligation under the CAA to adequately address the visibility
requirements of Part C of Title I of the CAA in its SIP and to prohibit
emissions from interfering with other states measures to protect
visibility. Thus, Executive Order 13132 does not apply to this action.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'', requires EPA to develop an
accountable process to ensure ``meaningful and timely input by tribal
officials in the development of regulatory policies that have tribal
implications.'' \247\ This proposed rule does not have tribal
implications, as specified in Executive Order 13175. It will not have
substantial direct effects on tribal governments. Thus, Executive Order
13175 does not apply to this rule.
---------------------------------------------------------------------------
\247\ 65 FR 67249, 67250 (Nov. 9, 2000).
---------------------------------------------------------------------------
G. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks
This action is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because the environmental health or safety risks
addressed by this action do not present a disproportionate risk to
children. Note, however, that emissions reductions achieved as a result
of this rule, under either proposal, will have a positive benefit on
children's health, as they are especially vulnerable to impacts from
emissions.
H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
This action is not subject to Executive Order 13211 (66 FR 28355
(May 22, 2001)), because it is not a significant regulatory action
under Executive Order 12866.
I. National Technology Transfer and Advancement Act
Section 12 of the National Technology Transfer and Advancement Act
(NTTAA) of 1995 requires Federal agencies to evaluate existing
technical standards when developing a new regulation. Section 12(d) of
NTTAA, Public Law 104-113, 12(d) (15 U.S.C. 272 note) directs EPA to
consider and use ``voluntary consensus standards'' in its regulatory
activities unless to do so would be inconsistent with applicable law or
otherwise impractical. Voluntary consensus standards are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
voluntary consensus standards bodies. NTTAA directs EPA to provide
Congress, through OMB, explanations when the Agency decides not to use
available and applicable voluntary consensus standards.
This proposed rulemaking does not involve technical standards.
Therefore, EPA is not considering the use of any voluntary consensus
standards.
J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations
Executive Order 12898, establishes federal executive policy on
environmental justice.\248\ Its main provision directs federal
agencies, to the greatest extent practicable and permitted by law, to
make environmental justice part of their mission by identifying and
addressing, as appropriate, disproportionately high and adverse human
health or environmental effects of their programs, policies, and
activities on minority populations and low-income populations in the
United States.
---------------------------------------------------------------------------
\248\ 59 FR 7629, 7629 (Feb. 16, 1994).
---------------------------------------------------------------------------
I certify that the approaches under this proposed rule will not
have potential disproportionately high and adverse human health or
environmental effects on minority, low-income or indigenous/tribal
populations. The results of this evaluation are available in the
docket. Both approaches would result in overall emission reductions for
NOX, SO2 and PM10 and therefore an
increase in the level of environmental protection for all affected
populations. EPA, however, will consider any input received during the
public comment period regarding environmental justice considerations.
Authority: 42 U.S.C. 7401 et seq.
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen dioxide, Particulate
matter, Sulfur oxides.
Dated: December 16, 2015.
Shaun L. McGrath,
Regional Administrator, Region 8.
For the reasons discussed in the preamble, the Environmental
Protection Agency proposes to amend 40 CFR part 52 as follows:
PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS
0
1. The authority citation for part 52 continues to read as follows:
Authority: 42 U.S.C. 7401 et seq.
Subpart TT--Utah
0
2. Add Sec. 52.2336 to read as follows:
Sec. 52.2336 Federal implementation plan for regional haze.
(a) Applicability. (1) This section applies to each owner and
operator of the following emissions units in the State of Utah:
(i) PacifiCorp Hunter Plant Units 1 and 2; and
(ii) PacifiCorp Huntington Plant Units 1 and 2.
(b) Definitions. Terms not defined here shall have the meaning
given them in the Clean Air Act or EPA's regulations implementing the
Clean Air Act. For purposes of this section:
(1) BART means Best Available Retrofit Technology.
(2) BART unit means any unit subject to a Regional Haze emission
limit in table 1 of this section.
(3) Continuous emission monitoring system or CEMS means the
equipment required by this section to sample, analyze, measure, and
provide, by means of readings recorded at least once every 15 minutes
(using an automated data acquisition and handling system (DAHS)), a
permanent record of NOX emissions, diluent, or stack gas
volumetric flow rate.
(4) FIP means Federal Implementation Plan.
(5) The term lb/MMBtu means pounds per million British thermal
units of heat input to the fuel-burning unit.
(6) NOX means nitrogen oxides.
(7) Operating day means a 24-hour period between 12 midnight and
the following midnight during which any fuel is combusted at any time
in the BART unit. It is not necessary for fuel to be combusted for the
entire 24-hour period.
(8) The owner/operator means any person who owns or who operates,
controls, or supervises a unit identified in paragraph (a) of this
section.
(9) Unit means any of the units identified in paragraph (a) of this
section.
(c) Emissions limitations. (1) The owners/operators of emissions
units subject to this section shall not emit, or cause to be emitted,
NOX in excess of the following limitations:
[[Page 2052]]
Table 1--to Sec. 52.2336--Emission Limits for BART Units
------------------------------------------------------------------------
NOX emission
limit--lb/
Source name/BART unit MMBtu (30-day
rolling
average)
------------------------------------------------------------------------
PacifiCorp Hunter Plant/Unit 1 \1\...................... 0.07
PacifiCorp Hunter Plant/Unit 2 \1\...................... 0.07
PacifiCorp Huntington Plant/Unit 1 \1\.................. 0.07
PacifiCorp Huntington Plant/Unit 2 \1\.................. 0.07
------------------------------------------------------------------------
\1\ The owners and operators of PacifiCorp Hunter Units 1 and 2 and
Huntington Units 1 and 2, shall comply with the NOX emission limit for
BART of 0.07 lb/MMBtu and other requirements of this section by [date
five years from the effective date of the final rule].
(2) These emission limitations shall apply at all times, including
startups, shutdowns, emergencies, and malfunctions.
(d) Compliance date. (1) The owners and operators of PacifiCorp
Hunter Units 1 and 2 shall comply with the NOX emission
limit of 0.07 lb/MMBtu and other requirements of this section by [date
five years from the effective date of the final rule]. The owners and
operators of PacifiCorp Huntington Units 1 and 2 shall comply with the
NOX emission limit of 0.07 lb/MMBtu and other requirements
of this section by [date five years from the effective date of the
final rule].
(e) Compliance determinations for NOX. (1) For all BART
units:
(i) CEMS. At all times after the earliest compliance date specified
in paragraph (d) of this section, the owner/operator of each unit shall
maintain, calibrate, and operate a CEMS, in full compliance with the
requirements found at 40 CFR part 75, to accurately measure
NOX, diluent, and stack gas volumetric flow rate from each
unit. The CEMS shall be used to determine compliance with the emission
limitations in paragraph (c) of this section for each unit.
(ii) Method. (A) For any hour in which fuel is combusted in a unit,
the owner/operator of each unit shall calculate the hourly average
NOX emission rate in lb/MMBtu at the CEMS in accordance with
the requirements of 40 CFR part 75. At the end of each operating day,
the owner/operator shall calculate and record a new 30-day rolling
average emission rate in lb/MMBtu from the arithmetic average of all
valid hourly emission rates from the CEMS for the current operating day
and the previous 29 successive operating days.
(B) An hourly average NOX emission rate in lb/MMBtu is
valid only if the minimum number of data points, as specified in 40 CFR
part 75, is acquired by both the pollutant concentration monitor
(NOX) and the diluent monitor (O2 or
CO2).
(C) Data reported to meet the requirements of this section shall
not include data substituted using the missing data substitution
procedures of subpart D of 40 CFR part 75, nor shall the data have been
bias adjusted according to the procedures of 40 CFR part 75.
(f) Recordkeeping. The owner/operator shall maintain the following
records for at least five years:
(1) All CEMS data, including the date, place, and time of sampling
or measurement; parameters sampled or measured; and results.
(2) Records of quality assurance and quality control activities for
emissions measuring systems including, but not limited to, any records
required by 40 CFR part 75.
(3) Records of all major maintenance activities conducted on
emission units, air pollution control equipment, and CEMS.
(4) Any other CEMS records required by 40 CFR part 75.
(g) Reporting. All reports under this section shall be submitted to
the Director, Office of Enforcement, Compliance and Environmental
Justice, U.S. Environmental Protection Agency, Region 8, Mail Code
8ENF-AT, 1595 Wynkoop Street, Denver, Colorado 80202-1129.
(1) The owner/operator of each unit shall submit quarterly excess
emissions reports for NOX BART units no later than the 30th
day following the end of each calendar quarter. Excess emissions means
emissions that exceed the emissions limits specified in paragraph (c)
of this section. The reports shall include the magnitude, date(s), and
duration of each period of excess emissions, specific identification of
each period of excess emissions that occurs during startups, shutdowns,
and malfunctions of the unit, the nature and cause of any malfunction
(if known), and the corrective action taken or preventative measures
adopted.
(2) The owner/operator of each unit shall submit quarterly CEMS
performance reports, to include dates and duration of each period
during which the CEMS was inoperative (except for zero and span
adjustments and calibration checks), reason(s) why the CEMS was
inoperative and steps taken to prevent recurrence, and any CEMS repairs
or adjustments. The owner/operator of each unit shall also submit
results of any CEMS performance tests required by 40 CFR part 75.
(3) When no excess emissions have occurred or the CEMS has not been
inoperative, repaired, or adjusted during the reporting period, such
information shall be stated in the quarterly reports required by
paragraphs (g)(1) and (2) of this section.
(h) Notifications. (1) The owner/operator shall promptly submit
notification of commencement of construction of any equipment which is
being constructed to comply with the NOX emission limits in
paragraph (c) of this section.
(2) The owner/operator shall promptly submit semi-annual progress
reports on construction of any such equipment.
(3) The owner/operator shall promptly submit notification of
initial startup of any such equipment.
(i) Equipment operation. At all times, the owner/operator shall
maintain each unit, including associated air pollution control
equipment, in a manner consistent with good air pollution control
practices for minimizing emissions.
(j) Credible evidence. Nothing in this section shall preclude the
use, including the exclusive use, of any credible evidence or
information, relevant to whether a source would have been in compliance
with requirements of this section if the appropriate performance or
compliance test procedures or method had been performed.
[FR Doc. 2015-33108 Filed 1-13-16; 8:45 am]
BILLING CODE 6560-50-P