Approval and Promulgation of Implementation Plans; Louisiana; Regional Haze State Implementation Plan, 22936-22949 [2017-10108]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 82, Number 96 (Friday, May 19, 2017)]
[Proposed Rules]
[Pages 22936-22949]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-10108]


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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R06-OAR-2017-0129; FRL-9961-28-Region 6]


Approval and Promulgation of Implementation Plans; Louisiana; 
Regional Haze State Implementation Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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

SUMMARY: Pursuant to the Federal Clean Air Act (CAA or the Act), the 
Environmental Protection Agency (EPA) is proposing to approve a portion 
of a revision to the Louisiana State Implementation Plan (SIP) 
submitted by the State of Louisiana through the Louisiana Department of 
Environmental Quality (LDEQ) on February 10, 2017, that addresses 
regional haze requirements for the first planning period. LDEQ 
submitted this SIP revision to address deficiencies identified by the 
EPA in a previous action. The EPA is proposing to approve the majority 
of the SIP revision, which addresses the CAA requirement that certain 
categories of existing major stationary sources built between 1962 and 
1977 procure and install the Best Available Retrofit Technology (BART), 
while deferring action on LDEQ's BART determination for a single 
facility. Specifically, the EPA is proposing to approve most of LDEQ's 
BART evaluations and conclusions for Louisiana's BART-eligible electric 
generating unit (EGU) sources and to approve LDEQ's sulfur-dioxide 
(SO2) and particulate-matter (PM) emission limits for those 
sources that are subject to BART. The EPA is also proposing to approve 
Louisiana's reliance on the Cross-State Air Pollution Rule (CSAPR) 
trading program for ozone-season nitrogen oxides (NOX) as a 
permissible alternative to source-specific NOX BART emission 
limits. This action is being taken under sections 110 and 169A of the 
CAA.

DATES: Written comments must be received on or before June 19, 2017.

ADDRESSES: Submit your comments, identified by Docket No. EPA-R06-OAR-
2017-0129, at https://www.regulations.gov or via email to 
R6_LA_BART@epa.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

[[Page 22937]]

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, please contact Jennifer 
Huser, huser.jennifer@epa.gov. For the full EPA public comment policy, 
information about CBI or multimedia submissions, and general guidance 
on making effective comments, please visit https://www2.epa.gov/dockets/commenting-epa-dockets.
    Docket: The index to the docket for this action is available 
electronically at www.regulations.gov and in hard copy at the EPA 
Region 6, 1445 Ross Avenue, Suite 700, Dallas, Texas. While all 
documents in the docket are listed in the index, some information may 
be publicly available only at the hard copy location (e.g., copyrighted 
material), and some may not be publicly available at either location 
(e.g., CBI).

FOR FURTHER INFORMATION CONTACT: Jennifer Huser, 214-665-7347, 
huser.jennifer@epa.gov. To inspect the hard copy materials, please 
schedule an appointment with Jennifer Huser or Mr. Bill Deese at 214-
665-7253.

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

Table of Contents

I. Background
    A. The Regional Haze Program
    B. Our Previous Actions on Louisiana Regional Haze
    C. CSAPR as an Alternative to Source-Specific NOX 
BART
II. Our Evaluation of Louisiana's BART Analysis
    A. Identification of BART-Eligible Sources
    B. Evaluation of Which Sources Are Subject to BART
    C. Sources That Are No Longer in Operation
    D. Sources That Screened Out of BART
    1. Visibility Impairment Threshold
    2. Model Plant Analysis
    3. CALPUFF Modeling To Screen Out Sources
    E. Subject to BART Sources
    1. Reliance on CSAPR To Satisfy NOX BART
    2. Sources That Deferred a Five-Factor Analysis Due to a Change 
in Operation
    3. Louisiana's Five-Factor Analyses for SO2 and PM 
BART
    a. Cleco Brame Energy Center
    b. Entergy Little Gypsy
    c. Entergy Ninemile Point
    d. Entergy Waterford
III. Proposed Action
IV. Statutory and Executive Order Reviews

I. Background

A. The Regional Haze Program

    Regional haze is visibility impairment that is produced by a 
multitude of sources and activities that are located across a broad 
geographic area and emit fine particulates (PM2.5) (e.g., 
sulfates, nitrates, organic carbon (OC), elemental carbon (EC), and 
soil dust), and their precursors (e.g., sulfur dioxide 
(SO2), nitrogen oxides (NOX), and in some cases, 
ammonia (NH3) and volatile organic compounds (VOCs)). 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 can be 
seen. PM2.5 can also cause serious adverse health effects 
and mortality in humans; it also contributes to environmental effects 
such as acid deposition and eutrophication.
    Data from the existing visibility monitoring network, ``Interagency 
Monitoring of Protected Visual Environments'' (IMPROVE), shows that 
visibility impairment caused by air pollution occurs virtually all the 
time at most national parks and wilderness areas. In 1999, the average 
visual range in many Class I areas (i.e., national parks and memorial 
parks, wilderness areas, and international parks meeting certain size 
criteria) in the western United States was 100-150 kilometers, or about 
one-half to two-thirds of the visual range that would exist without 
anthropogenic air pollution. In most of the eastern Class I areas of 
the United States, the average visual range was less than 30 
kilometers, or about one-fifth of the visual range that would exist 
under estimated natural conditions. CAA programs have reduced some 
haze-causing pollution, lessening some visibility impairment and 
resulting in partially improved average visual ranges.
    CAA requirements to address the problem of visibility impairment 
continue to be implemented. 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, man-made impairment of visibility in 156 
national parks and wilderness areas designated as mandatory Class I 
Federal areas. On December 2, 1980, EPA promulgated regulations to 
address visibility impairment in Class I areas that is ``reasonably 
attributable'' to a single source or small group of sources, i.e., 
``reasonably attributable visibility impairment.'' 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.
    Congress added section 169B to the CAA in 1990 to address regional 
haze issues, and EPA promulgated regulations addressing regional haze 
in 1999. The Regional Haze Rule revised the existing visibility 
regulations to add 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 our visibility protection regulations at 40 CFR 
51.300-309. The requirement to submit a regional haze SIP applies to 
all 50 states, the District of Columbia, and the Virgin Islands. States 
were required to submit the first implementation plan addressing 
regional haze visibility impairment no later than December 17, 2007.
    Section 169A of the CAA directs states to evaluate the use of 
retrofit controls at certain larger, often under-controlled, 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 toward the natural visibility goal, including 
a requirement that certain categories of existing major stationary 
sources built between 1962 and 1977 procure, install and operate the 
``Best Available Retrofit Technology'' (BART). Larger ``fossil-fuel 
fired steam electric plants'' are one of these source categories. Under 
the Regional Haze Rule, states are directed to conduct BART 
determinations for ``BART-eligible'' sources that may be anticipated to 
cause or contribute to any visibility impairment in a Class I area. The 
evaluation of BART for electric generating units (EGUs) that are 
located at fossil-fuel fired power plants having a generating capacity 
in excess of 750 megawatts must follow 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''). Rather 
than

[[Page 22938]]

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 for greater progress 
towards improving visibility than BART.

B. Our Previous Actions on Louisiana Regional Haze

    On June 13, 2008, Louisiana submitted a SIP to address regional 
haze (2008 Louisiana Regional Haze SIP or 2008 SIP revision). We acted 
on that submittal in two separate actions. Our first action was a 
limited disapproval \1\ because of deficiencies in the state's regional 
haze SIP submittal arising from the remand by the U.S. Court of Appeals 
for the District of Columbia of the Clean Air Interstate Rule (CAIR). 
Our second action was a partial limited approval/partial disapproval 
\2\ because the 2008 SIP revision met some but not all of the 
applicable requirements of the CAA and our regulations as set forth in 
sections 169A and 169B of the CAA and 40 CFR 51.300-308, but as a 
whole, the 2008 SIP revision strengthened the SIP. On August 11, 2016, 
Louisiana submitted a SIP revision to address the deficiencies related 
to BART for four non-EGU facilities. We proposed to approve that 
revision on October 27, 2016.\3\ On February 10, 2017, Louisiana 
submitted a SIP revision intended to address the deficiencies related 
to BART for EGU sources (2017 Louisiana Regional Haze SIP or 2017 SIP 
revision), a portion of which is the subject of this proposed action.
---------------------------------------------------------------------------

    \1\ 77 FR 33642 (June 7, 2012).
    \2\ 77 FR 39425 (July 3, 2012).
    \3\ 81 FR 74750 (October 27, 2016).
---------------------------------------------------------------------------

C. CSAPR as an Alternative to Source-Specific NOX BART

    In 2005, the EPA published CAIR, which required 28 states and the 
District of Columbia to reduce emissions of SO2 and 
NOX that significantly contribute to or interfere with 
maintenance of the 1997 national ambient air quality standards (NAAQS) 
for fine particulates and/or 8-hour ozone in any downwind state.\4\ EPA 
demonstrated that CAIR would achieve greater reasonable progress toward 
the national visibility goal than would BART; and therefore, states 
could rely on CAIR as an alternative to EGU BART for SO2 and 
NOX.\5\
---------------------------------------------------------------------------

    \4\ 70 FR 25161 (May 12, 2005).
    \5\ 70 FR 39104, 39139 (July 6, 2005).
---------------------------------------------------------------------------

    Louisiana's 2008 Regional Haze SIP relied on participation in CAIR 
as an alternative to meeting the source-specific EGU BART requirements 
for SO2 and NOX.\6\ Shortly after Louisiana 
submitted its SIP to us, however, the D.C. Circuit remanded CAIR 
(without vacatur).\7\ The court thereby left CAIR and CAIR Federal 
Implementation Plans (FIPs) in place in order to ``temporarily preserve 
the environmental values covered by CAIR'' until we could, by 
rulemaking, replace CAIR consistent with the court's opinion.\8\ In 
2011, we promulgated the Cross-State Air Pollution Rule (CSAPR) to 
replace CAIR.\9\ While EGUs in Louisiana were required to participate 
in CAIR for both SO2 and NOX, Louisiana EGUs are 
only included in CSAPR for ozone-season NOX.\10\
---------------------------------------------------------------------------

    \6\ See 40 CFR 51.308(e)(4) (2006).
    \7\ The court decided to vacate CAIR on July 11, 2008, and 
revised its decision, so as to remand the rule without vacatur, on 
December 23, 2008. North Carolina v. EPA, 531 F.3d 896, 901 (D.C. 
Cir. 2008), modified, 550 F.3d 1176 (D.C. Cir. 2008). Louisiana's 
initial Regional Haze SIP was submitted on June 13, 2008. 77 FR 
39425.
    \8\ 550 F.3d at 1178.
    \9\ 76 FR 48207 (August 8, 2011).
    \10\ 76 FR 82219, at 82226 (December 30, 2011).
---------------------------------------------------------------------------

    In 2012, we issued a limited disapproval of Louisiana's and several 
other states' regional haze SIPs because of reliance on CAIR as an 
alternative to EGU BART for SO2 and/or NOX.\11\ 
We also determined that CSAPR would provide for greater reasonable 
progress than BART and amended the Regional Haze Rule to allow CSAPR 
participation as an alternative to source-specific SO2 and/
or NOX BART for EGUs, on a pollutant-specific basis.\12\ 
Because Louisiana EGUs are included in CSAPR for NOX, 
Louisiana can rely on CSAPR better than BART for NOX. 
However, Louisiana's regional haze program must include source-by-
source EGU BART demonstrations for all other visibility impairing 
pollutants, namely, SO2 and PM.
---------------------------------------------------------------------------

    \11\ The limited disapproval triggered the EPA's obligation to 
issue a FIP or approve a SIP revision to correct the relevant 
deficiencies within 2 years of the final limited disapproval action. 
CAA section 110(c)(1); 77 FR 33642, at 33654 (August 6, 2012).
    \12\ While that rulemaking also promulgated FIPs for several 
states to replace reliance on CAIR with reliance on CSAPR as an 
alternative to BART, it did not include a FIP for Louisiana. 77 FR 
33642, 33654.
---------------------------------------------------------------------------

    CSAPR has been subject to extensive litigation, and on July 28, 
2015, the D.C. Circuit issued a decision generally upholding CSAPR but 
remanding without vacating the CSAPR emissions budgets for a number of 
states.\13\ We are in the process of responding to the remand of these 
CSAPR budgets. On October 26, 2016, we finalized an update to the CSAPR 
rule that addresses the 1997 ozone NAAQS portion of the remand and the 
CAA requirements addressing interstate transport for the 2008 ozone 
NAAQS.\14\ Additionally, three states, Alabama, Georgia, and South 
Carolina, have adopted or committed to adopt SIPs to replace the 
remanded FIPs and will continue the states' participation in the CSAPR 
program on a voluntary basis with the same budgets. On November 10, 
2016, we proposed a rule intended to address the remainder of the 
court's remand as it relates to Texas.\15\ This separate proposed rule 
includes an assessment of the impacts of the set of actions that the 
EPA has taken or expects to take in response to the D.C. Circuit's 
remand on our 2012 demonstration that participation in CSAPR provides 
for greater reasonable progress than BART. Based on that assessment, 
the EPA proposed that states may continue to rely on CSAPR as being 
better than BART on a pollutant-specific basis.
---------------------------------------------------------------------------

    \13\ Louisiana's ozone season NOX budgets were not 
included in the remand. EME Homer City Generation v. EPA, 795 F.3d 
118, 138 (D.C. Cir. 2015).
    \14\ 81 FR74504 (October 26, 2016).
    \15\ 81 FR 78954 (November 10, 2016).
---------------------------------------------------------------------------

II. Our Evaluation of Louisiana's BART Analysis

A. Identification of BART-Eligible Sources

    In our partial disapproval and partial limited approval of the 2008 
Louisiana Regional Haze SIP, we approved LDEQ's identification of 76 
BART-eligible sources.\16\ Table 1 lists the EGU sources that were 
identified in the 2008 Louisiana Regional Haze SIP submittal as BART-
eligible.
---------------------------------------------------------------------------

    \16\ See 77 FR 11839 at 11848 (February 28, 2012).

                              Table 1--Identification of BART-Eligible EGU Sources
----------------------------------------------------------------------------------------------------------------
              Facility name                            Units                              Parish
----------------------------------------------------------------------------------------------------------------
Cleco Rodemacher/Brame...................  Nesbitt I (Unit 1),           Rapides.
                                            Rodemacher II (Unit 2).

[[Page 22939]]

 
Cleco Teche..............................  Unit 3......................  St. Mary.
Entergy Sterlington......................  Unit 7......................  Ouachita.
Entergy Michoud..........................  Units 2 and 3...............  Orleans.
Entergy Waterford........................  Units 1, 2, and auxiliary     St. Charles.
                                            boiler.
Entergy Willow Glen......................  Units 2, 3, 4, 5, auxiliary   Iberville.
                                            boiler.
Entergy Ninemile Point...................  Units 4 and 5...............  Jefferson.
Entergy Nelson *.........................  Units 4, 6, and auxiliary     Calcasieu.
                                            boiler.
Entergy Little Gypsy.....................  Units 2, 3, and auxiliary     St. Charles.
                                            boiler.
Louisiana Generating (NRG) Big Cajun I...  Units 1 and 2...............  Point Coupee.
Louisiana Generating (NRG) Big Cajun II..  Units 1 and 2...............  Point Coupee.
Louisiana Energy and Power Authority       Boilers 1 and 2.............  Iberville.
 Plaquemine Steam Plant.
Louisiana Energy and Power Authority       Units 1, 2, 3, and 4 boilers  St. Mary/St. Martin.
 Morgan City Steam Plant.
City of Ruston--Ruston Electric            Boilers 1, 2, and 3.........  Lincoln.
 Generating Plant.
Lafayette Utilities System Louis ``Doc''   Units 1, 2, and 3...........  Lafayette.
 Bonin Electric Generating Station.
Terrebonne Parish Consolidated Government  Units 15 and 16.............  Terrebonne.
 Houma Generating Station.
City of Natchitoches Utility Department..  3 boilers...................  Natchitoches.
----------------------------------------------------------------------------------------------------------------
* We are not acting on BART determinations for Entergy Nelson in this action. We will address BART for Entergy
  Nelson in a future rulemaking.

B. Evaluation of Which Sources Are Subject to BART

    Because Louisiana's 2008 Regional Haze SIP relied on CAIR as better 
than BART for EGUs, the submittal did not include a determination of 
which BART-eligible EGUs were subject to BART. On May 19, 2015, we sent 
CAA Section 114 letters to several BART-eligible sources in Louisiana. 
In those letters, we noted our understanding that the sources were 
actively working with LDEQ to develop a SIP. However, in order to be in 
a position to develop a FIP should that be necessary, we requested 
information regarding the BART-eligible sources. The Section 114 
letters required sources to conduct modeling to determine if the 
sources were subject to BART, and included a modeling protocol. The 
letters also requested that a BART analysis be performed in accordance 
with the BART Guidelines for those sources determined to be subject to 
BART. We worked closely with those BART-eligible facilities and with 
LDEQ to this end, and all the information we received from the 
facilities was also sent to LDEQ. As a result, the LDEQ submitted a 
revised SIP submittal on February 10, 2017, that evaluates BART-
eligible EGUs in the State and provides a BART determination for each 
such source for all visibility impairing pollutants except 
NOX. This proposal addresses the entire 2017 Louisiana 
Regional Haze SIP, but for the portion concerning one BART-eligible EGU 
facility, specifically the Entergy Nelson facility. We will propose 
action on the Entergy Nelson portion of the SIP at a later date. We 
note that Louisiana unintentionally omitted discussion of two BART-
eligible facilities in its 2017 Louisiana Regional Haze SIP: Terrebonne 
Parish Consolidated Government Houma Generating Station and Louisiana 
Energy and Power Authority Plaquemine Steam Plant. We will address 
these two sources in the model plant analysis section below.

C. Sources That Are No Longer in Operation

    Several sources that were identified as BART-eligible have since 
retired from operation, rendering them no longer subject to the 
requirements of the Regional Haze Rule. For the units identified in the 
Table 2, the LDEQ provided documentation supporting permit rescissions 
to make these retirements permanent and enforceable.\17\
---------------------------------------------------------------------------

    \17\ See Appendix E of the 2017 Louisiana Regional Haze SIP for 
supporting documentation and the TSD for this action for additional 
information.

                                            Table 2--Retired Sources
----------------------------------------------------------------------------------------------------------------
              Facility name                            Units                              Parish
----------------------------------------------------------------------------------------------------------------
Louisiana Energy and Power Authority,      Units 1, 2, 3, and 4 boilers  St. Mary/St. Martin.
 Morgan City Steam Plant.
City of Ruston, Ruston Electric            Boilers 1, 2, and 3.........  Lincoln.
 Generating Plant.
City of Natchitoches Utility Department..  3 boilers...................  Natchitoches.
----------------------------------------------------------------------------------------------------------------

    In addition, Entergy Michoud Units 2 and 3 were identified as BART-
eligible, but are no longer in operation. By letter dated August 10, 
2016, Entergy System Operating Committee elected to permanently retire 
Michoud Units 2 and 3, effective June 1, 2016. This action was 
described in detail through a permit application to the state. As of 
the time of this proposal, LDEQ has not yet finalized that permit. The 
2017 Louisiana Regional Haze SIP includes the Air Permit Briefing Sheet 
that confirms Entergy's request to remove Units 2 and 3 from the 
permit.\18\ We propose to approve the SIP based on the draft permit, 
and note that we expect the proposed permit removing Units 2 and 3 to 
be final before we take final action to approve this portion of the 
2017 Louisiana Regional Haze SIP. Alternatively, LDEQ could submit 
another enforceable document to ensure that Units 2 and 3 cannot 
restart without a BART analysis and emission limits, or demonstrate the 
units have been deconstructed to the point that they cannot restart 
without obtaining a new NSR permit, making them not operational during 
the timeframe for BART eligibility.
---------------------------------------------------------------------------

    \18\ See Appendix D of the 2017 Louisiana Regional Haze SIP.

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

[[Page 22940]]

D. Sources That Screened Out of BART

    Once a list of BART-eligible sources still in operation within a 
state has been compiled, the state must determine whether to make BART 
determinations for all of them or to consider exempting some of them 
from BART because they are not reasonably anticipated to cause or 
contribute to any visibility impairment in a Class I area. The BART 
Guidelines present several options that rely on modeling analyses and/
or emissions analyses to determine if a source is not reasonably 
anticipated to cause or contribute to visibility impairment in a Class 
I area. A source that is not reasonably anticipated to cause or 
contribute to any visibility impairment in a Class I area is not 
``subject to BART,'' and for such sources, a state need not apply the 
five statutory factors to make a BART determination.\19\ Those sources 
are determined to be not subject to BART. Sources that are reasonably 
anticipated to cause or contribute to any visibility impairment in a 
Class I area are subject to BART.\20\ For each source subject to BART, 
40 CFR 51.308(e)(1)(ii)(A) requires that the LDEQ identify the level of 
control representing BART after considering the factors set out in CAA 
section 169A(g)(2). To determine which sources are anticipated to 
contribute to visibility impairment, the BART Guidelines state ``you 
can use CALPUFF or other appropriate model to estimate the visibility 
impacts from a single source at a Class I area.'' \21\
---------------------------------------------------------------------------

    \19\ See 40 CFR part 51, Appendix Y, III, How to Identify 
Sources ``Subject to BART''.
    \20\ Id.
    \21\ See 40 CFR part 51, Appendix Y, III, How to Identify 
Sources ``Subject to BART''.
---------------------------------------------------------------------------

1. Visibility Impairment Threshold
    The preamble to the BART Guidelines advises that, ``for purposes of 
determining which sources are subject to BART, States should consider a 
1.0 deciview \22\ change or more from an individual source to `cause' 
visibility impairment, and a change of 0.5 deciviews to `contribute' to 
impairment.'' \23\ It further advises that ``States should have 
discretion to set an appropriate threshold depending on the facts of 
the situation,'' and describes situations in which states may wish to 
exercise that discretion, mainly in situations in which a number of 
sources in an area are all contributing fairly equally to the 
visibility impairment of a Class I area. In Louisiana's 2008 Regional 
Haze SIP submittal, the LDEQ used a contribution threshold of 0.5 dv 
for determining which sources are subject to BART, and we approved this 
threshold in our previous action.\24\ The 2017 SIP revision includes a 
full five factor BART determination for each of the State's BART-
eligible EGUs whose visibility impacts exceed the 0.5 dv threshold.
---------------------------------------------------------------------------

    \22\ As we note in the Regional Haze Rule (64 FR 35725, July 1, 
1999), the ``deciview'' or ``dv'' is an atmospheric haze index that 
expresses changes in visibility. This visibility metric expresses 
uniform changes in haziness in terms of common increments across the 
entire range of visibility conditions, from pristine to extremely 
hazy conditions.
    \23\ 70 FR 39104, 39120 (July 6, 2005), [40 CFR part 51, 
Appendix Y].
    \24\ See, 77 FR 11839, 11849 (February 28, 2012).
---------------------------------------------------------------------------

2. Model Plant Analysis
    As part of our development of the BART Guidelines, we developed 
analyses of model plants with representative plume and stack 
characteristics for both EGU and non-EGU sources using the CALPUFF 
model.\25\ As we discuss in the BART Guidelines,\26\ based on those 
analyses, we believe that sources that emit less than 1,000 tons per 
year of NOX and SO2 and that are located more 
than 100 km from any Class I area can be exempted from the BART 
determination. The BART Guidelines note that the model plant concept 
can be extended using additional modeling analyses to ratios of 
emission levels and distances other than 1,000 tons/100 km. The BART 
Guidelines explain that: ``you may find based on representative plant 
analyses that certain types of sources are not reasonably anticipated 
to cause or contribute to visibility impairment. To do this, you may 
conduct your own modeling to establish emission levels and distances 
from Class I areas on which you can rely to exempt sources with those 
characteristics.'' \27\ Modeling analyses of representative plants are 
used to reflect groupings of specific sources with important common 
characteristics.
---------------------------------------------------------------------------

    \25\ CALPUFF Analysis in Support of the June 2005 Changes to the 
Regional Haze Rule, U.S. Environmental Protection Agency, June 15, 
2005, Docket No. OAR-2002-0076.
    \26\ 70 FR 39119 (July 6, 2005).
    \27\ 70 FR 39163 (July 6, 2005).
---------------------------------------------------------------------------

    As we mention above, we note that Louisiana unintentionally omitted 
discussion of two BART-eligible facilities in its 2017 Louisiana 
Regional Haze SIP: Terrebonne Parish Consolidated Government Houma 
Generating Station (Houma) and Louisiana Energy and Power Authority 
Plaquemine Steam Plant (Plaquemine). However, Louisiana's 2008 Regional 
Haze SIP submittal identified these two sources as BART-eligible, and 
we approved the inclusion of these two sources on that list in 
2012.\28\ The LDEQ has indicated that it inadvertently failed to 
address whether these two sources are subject to BART in the 2017 
Regional Haze SIP. These two sources were included in its 2008 Regional 
Haze SIP, but Louisiana relied on CAIR better than BART coverage for 
these sources when they adopted their 2008 SIP. Therefore, we have 
evaluated these two sources based on available information to determine 
whether they are subject to BART. We are not relying on the 1000 tpy/
100 km model plant approach but are instead relying on existing 
modeling included in the 2008 Louisiana Regional Haze SIP as being a 
representative plant analysis for the purpose of establishing emission 
levels and distances to exempt BART-eligible sources. Specifically, the 
2008 Louisiana Regional Haze SIP included review of CALPUFF modeling of 
a source owner, Valero, which demonstrated that Valero's BART-eligible 
sources do not cause or contribute to visibility impairment at the 
nearby Class I area, Breton National Wildlife Refuge (Breton). The 
Valero plant is representative (similar stack height and parameters) of 
the Houma and Plaquemine sources and can therefore be relied on in a 
model plant analysis to demonstrate that, based on baseline emissions 
and distance to the Class I area, the Houma and Plaquemine sources are 
not anticipated to cause or contribute to visibility impairment at 
Breton and are therefore not subject to BART.\29\ We analyzed the ratio 
of visibility impairing pollutants, denoted as `Q' (NOX, 
SO2, and PM-10 in tons/year) \30\ to the distance, denoted 
as `D' (distance of source to Breton in km). For example, if two 
sources were similar but one has a lower Q/D value, the lower ratio 
value (either due to lower emissions and/or greater distance) would be 
expected to have smaller visibility impacts at Breton. The Q/D ratio 
for Houma and Plaquemine are significantly lower compared to Valero's 
ratio (See Table 3). The Q/D ratios of Houma are approximately 20% of 
Valero's, and Plaquemine's ratio is less than 10% of Valero's Q/D 
ratio, and modeled impacts of the Valero source were less than the 0.5 
dv threshold.

[[Page 22941]]

Therefore, the data demonstrates that visibility impacts from the BART-
eligible units at Houma and Plaquemine are reasonably anticipated to be 
less than the modeled impacts from Valero and less than the 0.5 dv 
threshold to screen out. See the CALPUFF Modeling TSD for additional 
discussion of the model plant analysis.
---------------------------------------------------------------------------

    \28\ See Appendix E of the 2008 Louisiana RH SIP contained in 
the docket for the rulemaking at: 77 FR 11839, 11848.
    \29\ See 40 CFR part 51 Appendix Y.
    \30\ To calculate Q, the maximum 24-hr emissions for 
NOX, SO2 and PM from the 2000-2004 baseline 
were identified for each BART-eligible unit at a source (See Table 
9.3 of the 2008 Louisiana RH SIP). Emissions are not paired in time 
(i.e. max 24- hour NOX emissions value would not usually 
be on the same day as max 24-hour SO2 emissions). The sum 
of these daily max NOX, PM and SO2 emissions 
were summed and then multiplied by 365 days.
---------------------------------------------------------------------------

    We also note that on December 11, 2015, the Lafayette Utilities 
System Louis ``Doc'' Bonin Generating Station advised our Clean Air 
Markets Division that: Unit 1 last operated on June 22, 2011, and was 
put into cold storage on June 1, 2013; Unit 2 last operated on July 5, 
2013, and was put into cold storage on June 29, 2014; and Unit 3 last 
operated on August 27, 2013, and was put into cold storage on June 24, 
2014. The Midcontinent Independent System Operator (MISO) is currently 
conducting a study to predict the future use of these unit(s) for 
peaking purposes. If it is determined that these units are no longer 
necessary to facilitate electrical power generation, they will be 
retired.\31\ However, at this time Lafayette Utilities System has not 
yet submitted a request to rescind the permit for the Louis ``Doc'' 
Bonin Electric Generating Station. Because placing the units in cold 
storage is not a permanent and enforceable closure under the Regional 
Haze requirements, we included Louis ``Doc'' Bonin in our model plant 
analysis. The Q/D ratio for Louis ``Doc'' Bonin is significantly lower 
compared to Valero's Q/D ratio (See Table 3). The ratio is less than 
40% of Valero's ratio and modeled impacts of the Valero source were 
less than the 0.5 dv threshold, which demonstrates that visibility 
impairment from the BART-eligible units at Louis ``Doc'' Bonin are 
reasonably anticipated to be less than the modeled impacts from Valero 
and below the 0.5 dv threshold to screen out. The model plant analysis 
demonstrates that, based on baseline emissions, the source is not 
anticipated to cause or contribute to visibility impairment of any 
Class I area, and is therefore not subject to BART. See the CALPUFF 
Modeling TSD for additional discussion of the model plant analysis. 
Because the modeling results demonstrate that Louis ``Doc'' Bonin is 
not subject to BART, we propose to approve this portion of the 2017 
Louisiana Regional Haze SIP.
---------------------------------------------------------------------------

    \31\ See Appendix E of the 2017 Louisiana Regional Haze SIP.

                                                             Table 3--Model Plant Q/D Ratios
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                        Facility                                 Max
                              Facility                               NOX (TPY)  SOX (TPY)   PM (TPY)   emissions   Distance to   Q/D (TPY/    percentile
                                                                                                         (TPY)     Breton (km)      km)        Delta DV
--------------------------------------------------------------------------------------------------------------------------------------------------------
Terrebonne Parish Consolidated Government Houma Generating Station.      909.8       3.65        7.3       930.75          165         5.64
Louisiana Energy and Power Authority Plaquemine Steam Plant........     492.75          0          0       492.75        227.1         2.17
Lafayette Utilities System Louis ``Doc'' Bonin Electric Generating        2993        7.3      109.5       3109.8        298.9        10.04
 Station...........................................................
Valero.............................................................       1876       1091      401.5       3368.5        139.3        24.18        0.484
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Based on the results of this analysis, we propose that the BART-
eligible sources identified in Table 4 are not reasonably anticipated 
to cause or contribute to the visibility impairment at a Class I area 
and are not subject to BART.

                            Table 4--Sources Screened Out Using Model Plant Analysis
----------------------------------------------------------------------------------------------------------------
              Facility Name                            Units                              Parish
----------------------------------------------------------------------------------------------------------------
Louisiana Energy and Power Authority       Boilers 1 and 2.............  Iberville.
 Plaquemine Steam Plant.
Lafayette Utilities System Louis ``Doc''   Units 1, 2, and 3...........  Lafayette.
 Bonin Electric Generating Station.
Terrebonne Parish Consolidated Government  Units 15 and 16.............  Terrebonne.
 Houma Generating Station.
----------------------------------------------------------------------------------------------------------------

3. CALPUFF Modeling To Screen Out Sources
    Some sources were modeled directly with CALPUFF to determine 
whether the BART-eligible source causes or contributes to visibility 
impairment in nearby Class I areas. The maximum 98th percentile impact 
from the modeled years (calculated based on annual average natural 
background conditions) was compared with the 0.5 dv screening threshold 
following the modeling protocol described in the CALPUFF Modeling TSD. 
The BART Guidelines recommend that states use the 24-hour average 
actual emission rate from the highest emitting day of the 
meteorological period modeled, unless this rate reflects periods of 
start-up, shutdown, or malfunction. The maximum 24-hour emission rate 
(lb/hr) for NOX and SO2 from the initial baseline 
period (with the noted difference for Big Cajun II discussed below) for 
each source was identified through a review of the daily emission data 
for each BART-eligible unit from EPA's Air Markets Program Data.\32\ 
See the CALPUFF Modeling TSD for additional discussion and model 
results for this portion of the screening analysis.
---------------------------------------------------------------------------

    \32\ https://ampd.epa.gov/ampd/.
---------------------------------------------------------------------------

    As previously discussed, LDEQ submitted its initial Regional Haze 
SIP in 2008 and relied on CAIR as a substitute for BART for 
SO2 and NOX for all of its BART-eligible EGUs. 
Due to reliance on CAIR, that SIP submittal did not include a 
determination of which BART-eligible EGUs were subject to BART. EPA's 
limited disapproval of Louisiana's Regional Haze SIP due to the State's 
reliance on CAIR revived Louisiana's obligation to provide a SIP to 
fully address EGU BART.\33\ While Louisiana's 2017 Regional Haze SIP 
revision relies on CSAPR for EGU BART for NOX, it does not 
provide an alternative to source-by-source EGU BART for SO2 
and PM. Therefore, Louisiana's 2017 Regional Haze SIP revision included 
modeling of the impacts of the 24-hour maximum emission rate during the 
2000-2004

[[Page 22942]]

baseline period (with the noted exception of Big Cajun II discussed 
below) of all visibility-impairing pollutants from all BART-eligible 
units at the facility. BART-eligible sources with visibility impacts 
above the 0.5 dv threshold are subject to BART.
---------------------------------------------------------------------------

    \33\ 77 FR 33642 (June 7, 2012).
---------------------------------------------------------------------------

    The Big Cajun II Power Plant is a coal-fired power station owned 
and operated by Louisiana Generating, LLC, (a subsidiary of NRG 
Energy). In our prior action on the 2008 Regional Haze SIP submittal, 
we approved Louisiana's determination that Big Cajun II has two BART-
eligible units, Unit 1 and Unit 2.\34\ Unit 1 is a coal-fired unit, and 
Unit 2 was formerly a coal-fired unit but is now a gas-fired unit. The 
LDEQ's screening modeling for Big Cajun II accounted for current 
operating conditions at the facility. The modeling analysis was 
conducted using the current enforceable short term emission limits from 
the facility that reflect controls installed after the 2008 Regional 
Haze SIP submittal.
---------------------------------------------------------------------------

    \34\ See TSD Table 6 in the Rulemaking Docket numbered EPA-R06-
OAR-2008-0510.
---------------------------------------------------------------------------

    On March 6, 2013, Louisiana Generating entered a consent decree 
(CD) with EPA, the LDEQ, and others to resolve a complaint filed 
against Louisiana Generating for several violations of the CAA at Big 
Cajun II. U.S. et al v. Louisiana Generating, LLC, Civil Action No. 09-
100-JJB-RLB (M.D. La.). Among other things, the CD requires Louisiana 
Generating to refuel Big Cajun II Unit 2 to natural gas, and install 
and continuously operate dry sorbent injection (DSI) at Big Cajun II 
Unit 1 while maintaining a 30-day rolling average SO2 
emission rate of no greater than 0.380 lb/MMBtu by no later than April 
15, 2015.\35\ Prior to the submittal of the 2017 Regional Haze SIP, the 
LDEQ and Louisiana Generating entered into an Agreed Order on Consent 
(AOC) that made these existing control requirements and maximum daily 
emission limits permanent and enforceable for BART. The AOC is included 
in Louisiana's 2017 SIP revision. Thus, if the EPA finalizes its 
proposed approval of this portion of the SIP submittal, the control 
requirements and emission limits will become permanent and federally 
enforceable for purposes of regional haze. As these controls were not 
installed to meet BART requirements, and existing enforceable emission 
limits for Units 1 and 2 prevent the source from emitting at levels 
seen during the 2000-2004 baseline, LDEQ's screening modeling in the 
2017 Regional Haze SIP submittal utilizes the current daily emission 
limits for these units in the AOC as representative of the anticipated 
24-hr maximum emissions for screening modeling purposes. LDEQ's 
modeling demonstrates that, based on these existing controls and 
enforceable emission limits, Big Cajun II contributes less than 0.5 dv 
at all impacted Class I areas, and therefore the facility is not 
subject to BART.
---------------------------------------------------------------------------

    \35\ CD paragraph 62 in the docket for this rulemaking.
---------------------------------------------------------------------------

    It should be noted that in addition to requiring DSI, the 
applicable enforcement CD requires Louisiana Generating to retire, 
refuel, repower, or retrofit Big Cajun II Unit 1 by no later than April 
1, 2025. Louisiana Generating must notify us of which option it will 
select to comply with this condition no later than December 31, 2022, 
and any option taken would produce significantly fewer emissions.\36\
---------------------------------------------------------------------------

    \36\ CD paragraph 63 in the docket for this rulemaking.
---------------------------------------------------------------------------

    With the use of CALPUFF modeling results, Louisiana concluded, and 
we are proposing to agree, that the facilities listed in Table 5 have 
visibility impacts of less than 0.5 dv,\37\ and therefore, are not 
subject to BART:
---------------------------------------------------------------------------

    \37\ In our previous action on Louisiana Regional Haze, we 
approved Louisiana's selection of 0.5 dv as the threshold for 
screening out BART-eligible sources. See 77 FR 11839, 11848.

                           Table 5--Sources With Visibility Impact of Less Than 0.5 dv
----------------------------------------------------------------------------------------------------------------
              Facility name                            Units                              Parish
----------------------------------------------------------------------------------------------------------------
Cleco Teche..............................  Unit 3......................  St. Mary.
Entergy Sterlington......................  Unit 7......................  Ouachita.
Louisiana Generating (NRG) Big Cajun I...  Units 1 and 2...............  Point Coupee.
Louisiana Generating (NRG) Big Cajun II..  Units 1 and 2...............  Pointe Coupee.
----------------------------------------------------------------------------------------------------------------

E. Subject to BART Sources

    With the use of CALPUFF modeling results as discussed above, 
Louisiana concluded, and we are proposing to agree, that the facilities 
listed in Table 6 have visibility impacts greater than 0.5 dv. These 
facilities are therefore subject to BART and must undergo a five-factor 
analysis. See the CALPUFF Modeling TSD for our review of CALPUFF 
modeling in the 2017 Louisiana Regional Haze SIP.

                           Table 6--Subject to BART Sources Addressed in This Proposal
----------------------------------------------------------------------------------------------------------------
              Facility name                            Units                              Parish
----------------------------------------------------------------------------------------------------------------
Cleco Rodemacher/Brame...................  Nesbitt I (Unit 1),           Rapides.
                                            Rodemacher II (Unit 2).
Entergy Waterford........................  Units 1, 2, and auxiliary     St. Charles.
                                            boiler.
Entergy Willow Glen......................  Units 2, 3, 4, 5, and         Iberville.
                                            auxiliary boiler.
Entergy Ninemile Point...................  Units 4 and 5...............  Jefferson.
Entergy Little Gypsy.....................  Units 2, 3, and auxiliary     St. Charles.
                                            boiler.
----------------------------------------------------------------------------------------------------------------

    We note that in addition to the CALPUFF modeling included in the 
2017 Louisiana Regional Haze SIP submittal, the results of CAMx 
modeling performed by Trinity consultants was included in the submittal 
as additional screening analyses \38\ that purport to demonstrate that 
the baseline visibility impacts from Cleco Brame and a

[[Page 22943]]

number of the Entergy sources \39\ are significantly less than the 0.5 
dv threshold established by Louisiana. However, this modeling was not 
conducted in accordance with the BART Guidelines and a previous 
modeling protocol developed for the use of CAMx modeling for BART 
screening (EPA, Texas and FLM representatives 
approved),40 41 and does not properly assess the maximum 
baseline impacts. Therefore, we agree with LDEQ's decision to not rely 
on this CAMx modeling, but rather rely on the CALPUFF modeling for BART 
determinations.\42\ We provide a detailed discussion of our review of 
this CAMx modeling in the CAMx Modeling TSD. We also note that for the 
largest emission sources, those with coal-fired units, we performed our 
own CAMx modeling following the BART Guidelines and consistent with 
previously agreed techniques and metrics of the Texas CAMx BART 
screening protocol to provide additional information on visibility 
impacts and impairment and address possible concerns with utilizing 
CALPUFF to assess visibility impacts at Class I areas located farther 
from the emission sources. See the CAMx Modeling TSD for additional 
information on EPA's CAMx modeling protocol, inputs, and model results.
---------------------------------------------------------------------------

    \38\ See October 10, 2016 Letter from Cleco Corporation to 
Vivian Aucoin and Vennetta Hayes, LDEQ, RE: Cleco Corporation 
Louisiana BART CAMx Modeling, included in Appendix B of the 2017 
Louisiana Regional Haze SIP submittal; CAMx Modeling Report, 
prepared for Entergy Services by Trinity Consultants, Inc. and All 4 
Inc, October 14, 2016, included in Appendix D of the 2017 Louisiana 
Regional Haze SIP submittal.
    \39\ Entergy's CAMx modeling included model results for Michoud, 
Little Gypsy, R.S. Nelson, Ninemile Point, Willow Glen, and 
Waterford.
    \40\ Texas had over 120 BART-eligible facilities located at a 
wide range of distances to the nearest class I areas in their 
original Regional Haze SIP. Due to the distances between sources and 
Class I areas and the number of sources, Texas worked with EPA and 
FLM representatives to develop a modeling protocol to conduct BART 
screening of sources using CAMx photochemical modeling. Texas was 
the only state that screened sources using CAMx and had a protocol 
developed for how the modeling was to be performed and what metrics 
had to be evaluated for determining if a source screened out. See 
Guidance for the Application of the CAMx Hybrid Photochemical Grid 
Model to Assess Visibility Impacts of Texas BART Sources at Class I 
Areas, ENVIRON International, December 13, 2007, available in the 
docket for this action.
    \41\ EPA, the Texas Commission on Environmental Quality (TCEQ), 
and FLM representatives verbally approved the approach in 2006 and 
in email exchange with TCEQ representatives in February 2007 (see 
email from Erik Snyder (EPA) to Greg Nudd of TCEQ Feb. 13, 2007 and 
response email from Greg Nudd to Erik Snyder Feb. 15, 2007, 
available in the docket for this action).
    \42\ See Response to Comments in Appendix A of the 2017 
Louisiana Regional Haze SIP submittal.
---------------------------------------------------------------------------

1. Reliance on CSAPR To Satisfy NOX BART
    Louisiana's 2017 Regional Haze SIP submittal relies on CSAPR better 
than BART for NOX for EGUs. We propose to find that the 
NOX BART requirements for EGUs in Louisiana will be 
satisfied by our determination, proposed for separate finalization, 
that Louisiana's participation in CSAPR's ozone-season NOX 
program is a permissible alternative to source-specific NOX 
BART. We cannot finalize this portion of the proposed SIP approval 
unless and until we finalize the proposed finding that CSAPR continues 
to be better than BART \43\ because finalization of that proposal 
provides the basis for Louisiana to rely on CSAPR participation as an 
alternative to source-specific EGU BART for NOX.
---------------------------------------------------------------------------

    \43\ 81 FR 78954.
---------------------------------------------------------------------------

2. Sources That Deferred a Five-Factor Analysis Due to a Change in 
Operation
    Entergy operates five BART-eligible units at the Willow Glen 
Electric Generating Plant (Willow Glen) in Iberville Parish, Louisiana, 
all of which burn natural gas. Unit 2 is an EGU boiler with a maximum 
heat input capacity of 2,188 MMBtu/hr. Unit 3 is an EGU boiler with a 
maximum heat input capacity of 5,900 MMBtu/hr. Unit 4 is an EGU boiler 
with a maximum heat input capacity of 5,400 MMBtu/hr. Unit 5 is an EGU 
boiler with a maximum heat input capacity of 5,544 MMBtu/hr. Unit 3 
also has an auxiliary boiler with a maximum heat input capacity of 206 
MMBtu/hr, which is itself BART-eligible. All of these units are also 
permitted to burn fuel oil, but none has done so in several years. 
Entergy has no operational plans to burn oil at these units in the 
future. Entergy's analysis, included in the 2017 Louisiana Regional 
Haze SIP Appendix D, addresses BART for the natural-gas-firing scenario 
and does not consider emissions from fuel-oil firing. Entergy's 
analysis states that if conditions change such that it becomes economic 
to burn fuel oil, the facility will submit a five-factor BART analysis 
for the fuel-oil firing scenario to Louisiana to be submitted to us as 
a SIP revision. Until such a SIP revision is approved, the 2017 
Louisiana Regional Haze SIP precludes fuel-oil combustion at the Willow 
Glen facility. To make the prohibition on fuel-oil usage at Willow Glen 
enforceable, Entergy and LDEQ entered an AOC, included in the SIP that 
establishes the following requirement:

    Before fuel oil firing is allowed to take place at Units 2, 3, 
4, 5, and the auxiliary boiler at the Facility, a revised BART 
determination must be promulgated for SO2 and PM for the 
fuel oil firing scenario through a FIP or an action by the LDEQ as a 
SIP revision and approved by EPA such that the action will become 
federally enforceable.\44\
---------------------------------------------------------------------------

    \44\ See AOC in Appendix D of the 2017 Louisiana Regional Haze 
SIP submittal.

    With our final approval of this portion of the SIP submittal, the 
conditions in the AOC will become federally enforceable for purposes of 
regional haze. We propose to find that this approach is adequate to 
address BART.\45\
---------------------------------------------------------------------------

    \45\ Under the AOC, if any of the five units at Willow Glen 
decides to burn fuel oil, Entergy will complete a BART analysis for 
each pollutant for the fuel oil firing scenario and submit the 
analysis to the State. Upon receiving Entergy's submission 
indicating that the units intend to switch to fuel oil, the State 
will submit a SIP revision with BART determinations for the fuel oil 
firing scenario for the units intending to switch to fuel oil. The 
sources will not begin to burn fuel oil until we have approved the 
submitted SIP revision containing the BART determinations.
---------------------------------------------------------------------------

    With regard to BART requirements for the gas-firing scenario, 
SO2 and PM emissions for the gas-only fired units that are 
subject to BART are inherently low,\46\ and are so minimal that the 
installation of any additional PM or SO2 controls on these 
units would likely achieve very small emissions reductions and have 
minimal visibility benefits. As there are no appropriate add-on 
controls and the status quo reflects the most stringent controls, we 
propose to agree with Louisiana that SO2 and PM BART is no 
additional controls for the Willow Glen units when burning natural gas.
---------------------------------------------------------------------------

    \46\ AP 42, Fifth Edition, Volume 1, Chapter 1: External 
Sources, Section 1.4, Natural Gas Combustion, available here: 
https://www3.epa.gov/ttn/chief/ap42/ch01/final/c01s04.pdf.
---------------------------------------------------------------------------

3. Louisiana's Five-Factor Analyses for SO2 and PM BART
    In determining BART, the state must consider the five statutory 
factors in section 169A 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). All units 
that are subject to BART must undergo a BART analysis. The BART 
Guidelines break the analysis down into five steps: \47\
---------------------------------------------------------------------------

    \47\ 70 FR 39103, 39164 (July 6, 2005) [40 CFR 51, App. Y].

    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

[[Page 22944]]

    STEP 5--Evaluate Visibility Impacts.

    As mentioned previously, we disapproved portions of Louisiana's 
2008 Regional Haze SIP due to the state's reliance on CAIR as an 
alternative to source-by-source BART for EGUs.\48\ Following our 
limited disapproval, LDEQ worked closely with the BART-eligible 
facilities and with us to revise its Regional Haze SIP, which resulted 
in the submittal of its 2017 Regional Haze SIP. The 2017 SIP submittal 
includes, among other things, a five-factor BART analysis for each 
subject to BART source for PM and SO2. Louisiana's 2017 
Regional Haze SIP relies on CSAPR participation as an alternative to 
source-specific EGU BART for NOX. In evaluating the State's 
2017 SIP revision, we reviewed each BART analysis for SO2 
and PM for each subject to BART source and other relevant information 
provided in the 2017 Regional Haze SIP submittal.
---------------------------------------------------------------------------

    \48\ 77 FR 33642.
---------------------------------------------------------------------------

a. Cleco Brame Energy Center
    The Cleco Brame Energy Center includes two units that are subject 
to BART. Nesbitt 1 (Brame Unit 1) is a 440-megawatt (MW) EGU boiler 
that burns natural gas and is not equipped with any air pollution 
controls. Rodemacher 2 (Brame Unit 2) is a 523 MW wall-fired EGU boiler 
that burns Powder River Basin (PRB) coal. Cleco submitted a BART 
screening analysis to us and LDEQ on August 31, 2015, and a BART five-
factor analysis dated October 31, 2015, revised April 14, 2016 and 
April 18, 2016 in response to an information request.\49\ These 
analyses were adopted and incorporated into Louisiana's 2017 Regional 
Haze SIP (Appendix B).
---------------------------------------------------------------------------

    \49\ Wren Stenger, Section 114(a) Information Request letter to 
Darren Olagues (Cleco), May 19, 2015.
---------------------------------------------------------------------------

Nesbitt 1
    Nesbitt 1 is currently permitted to burn natural gas and oil. 
However, this unit has not burned oil in the recent past. LDEQ did not 
conduct a five-factor BART analysis for Nesbitt 1, concluding that 
``SO2 BART controls are satisfied through the conversion to 
natural gas.'' \50\ The preamble to the BART Guidelines states: \51\
---------------------------------------------------------------------------

    \50\ See Cleco BART Analysis in Appendix B of the 2017 Louisiana 
Regional Haze SIP.
    \51\ 70 FR 39116.

    Consistent with the CAA and the implementing regulations, States 
can adopt a more streamlined approach to making BART determinations 
where appropriate. Although BART determinations are based on the 
totality of circumstances in a given situation, such as the distance 
of the source from a Class I area, the type and amount of pollutant 
at issue, and the availability and cost of controls, it is clear 
that in some situations, one or more factors will clearly suggest an 
outcome. Thus, for example, a State need not undertake an exhaustive 
analysis of a source's impact on visibility resulting from 
relatively minor emissions of a pollutant where it is clear that 
controls would be costly and any improvements in visibility 
resulting from reductions in emissions of that pollutant would be 
negligible. In a scenario, for example, where a source emits 
thousands of tons of SO2 but less than one hundred tons 
of NOX, the State could easily conclude that requiring 
expensive controls to reduce NOX would not be 
---------------------------------------------------------------------------
appropriate.

    SO2 and PM emissions from gas-fired units are inherently 
low,\52\ so the installation of any additional PM or SO2 
controls on this unit would likely achieve very small emissions 
reductions and have minimal visibility benefits.
---------------------------------------------------------------------------

    \52\ AP 42, Fifth Edition, Volume 1, Chapter 1: External 
Sources, Section 1.4, Natural Gas Combustion, available here: 
https://www3.epa.gov/ttn/chief/ap42/ch01/final/c01s04.pdf.
---------------------------------------------------------------------------

    Before burning fuel oil at this unit, Cleco has committed to submit 
a five-factor BART analysis for the fuel-oil-firing scenario to 
Louisiana to be submitted to us as a SIP revision, and fuel oil 
combustion will not take place until our final approval of that SIP 
revision. To make the prohibition on fuel-oil usage at this unit 
enforceable, Cleco and LDEQ entered an AOC that establishes enforceable 
limits, consistent with the exclusive use of natural gas, of 3.0 lb/hr 
SO2 and 37.3 lb/hr PM10 on 30-day rolling 
averages and a limitation on Nesbitt 1 analogous to the limitation for 
Willow Glen discussed previously.\53\ This AOC is included in 
Louisiana's 2017 SIP revision. With our final approval of this portion 
of the 2017 SIP submittal and the AOC, that limitation will become 
federally enforceable for purposes of Regional Haze. We propose to find 
this approach adequate to meet BART.
---------------------------------------------------------------------------

    \53\ See AOC in Appendix B of the 2017 Louisiana Regional Haze 
SIP.
---------------------------------------------------------------------------

Rodemacher 2
    As the 2017 Louisiana Regional Haze SIP indicates,\54\ recent 
pollution control upgrades at Rodemacher 2 include:
---------------------------------------------------------------------------

    \54\ See BART Analysis in Appendix B of the 2017 Louisiana 
Regional Haze SIP.

     Low-NOX burners (LNB) installed in 2008;
     Low-sulfur coal combustion starting in 2009;
     Selective non-catalytic reduction (SNCR) installed in 
2014; and
     DSI, activated carbon injection (ACI), and a fabric 
filter baghouse installed in 2015.

    In assessing SO2 BART, Cleco considered the five BART 
factors we discuss above. In assessing feasible control technologies 
and their effectiveness, Cleco considered an enhancement to the 
existing DSI system, dry scrubbing (spray dry absorption, or SDA), and 
wet scrubbing (wet flue gas desulfurization, or wet FGD). In 
considering enhanced DSI, Cleco relied upon on-site testing it had 
conducted to determine the performance potential of an enhanced DSI 
system. The testing was conducted to evaluate the effectiveness of the 
DSI system to control hydrochloric acid for compliance with the Mercury 
and Air Toxics Standards (MATS), but the continuous emissions monitor 
system (CEMS) was operating and capturing SO2 emissions data 
during the test, which provided the necessary information to determine 
the control efficiency of DSI and enhanced DSI for SO2.\55\ 
As a result of this testing, Cleco determined that the current and 
enhanced DSI systems have SO2 removal efficiencies of 
approximately 39% and 63%, respectively, with the enhanced DSI system 
being capable of meeting a monthly SO2 emission limit of 
0.30 lbs/MMBtu. Cleco secured this limit as part of the same AOC 
referenced above for the Nesbitt 1. Cleco also assessed SDA and wet FGD 
as being capable of meeting emission limits of 0.06 and 0.04 lbs/MMBtu, 
respectively.
---------------------------------------------------------------------------

    \55\ See the April 5, 2016 letter to Guy Donaldson from Bill 
Matthews in our docket.
---------------------------------------------------------------------------

    In considering the costs of compliance for these controls, Cleco 
concluded that the enhanced DSI system would not require any additional 
capital expenses, but would require additional operating costs due to 
the need for additional sorbent (trona). Cleco didn't specifically 
address the energy impacts and non-air quality impacts of enhanced DSI, 
but we conclude that any considerations regarding these factors would 
be very minimal over the already installed DSI system. Cleco also 
assessed the costs associated with installing and operating SDA and wet 
FGD, as discussed below. In regards to energy impacts and non-air 
quality impacts, Cleco concluded that wet FGD poses certain water and 
waste disposal problems over SDA. Cleco concluded that remaining useful 
life was not an important factor for any of the control scenarios.
    In assessing visibility impacts, the state's submittal included 
CALPUFF modeling evaluating the visibility benefits of DSI, enhanced 
DSI, SDA, and wet FGD. We summarize the results of that modeling in 
Table 7.
---------------------------------------------------------------------------

    \56\ DSI modeled at 0.41 lb/MMBtu, DSI and fabric filter are 
already installed and operational.

[[Page 22945]]



               Table 7--Anticipated Visibility Benefit Due to Controls on Cleco Rodemacher Unit 2
                                           [CALPUFF, 98th percentile]
----------------------------------------------------------------------------------------------------------------
                                                         Visibility benefit of controls over baseline (dv)
          Class I area               Baseline    ---------------------------------------------------------------
                                    impact (dv)      DSI \56\      Enhanced DSI         SDA            WFGD
----------------------------------------------------------------------------------------------------------------
Breton..........................           0.724           0.134           0.226           0.436           0.445
Caney Creek.....................           0.734           0.085           0.122           0.311           0.322
----------------------------------------------------------------------------------------------------------------

    Enhanced DSI achieves benefits of approximately 0.092 dv at Breton 
and 0.037 dv at Caney Creek Wilderness (Caney Creek) over DSI and 
benefits of 0.226 dv at Breton and 0.122 dv at Caney Creek over the 
baseline impairment. The visibility benefits of SDA and wet FGD exceed 
the benefits from enhanced DSI by approximately 0.2 dv at Caney Creek 
and Breton.
    We also performed our own CAMx modeling analysis for Cleco 
Rodemacher Unit 2 following the BART Guidelines to evaluate the maximum 
baseline visibility impacts and potential benefits from two levels of 
controls, DSI at 0.41 lb/MMBtu and wet FGD at 0.04 lb/MMBtu, to 
supplement the CALPUFF modeling. As discussed above, Louisiana relied 
on CALPUFF modeling to inform BART determinations consistent with the 
BART Guidelines. However, the use of CALPUFF is typically used for 
distances less than 300-400 km. The Cleco Brame source is located 352 
km from Caney Creek and 422 km from Breton. CAMx provides a 
scientifically validated platform for assessment of visibility impacts 
over a wide range of source-to-receptor distances. CAMx is also more 
suited than some other modeling approaches for evaluating the impacts 
of SO2, NOX, VOC, and PM emissions as it has a 
more robust chemistry mechanism than CALPUFF. Our CAMx Modeling TSD 
provides a detailed description of the modeling protocol, model inputs, 
and model results, the latter of which is summarized in Table 8.
---------------------------------------------------------------------------

    \57\ DSI modeled at 0.41 lb/MMBtu, DSI and fabric filter are 
already installed and operational.
    \58\ DSI modeled at 0.41 lb/MMBtu, DSI and fabric filter are 
already installed and operational.

                                   Table 8--Anticipated Visibility Benefit Due to Controls on Cleco Rodemacher Unit 2
                                                                         [CAMX]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                             Baseline     Visibility benefit of controls  Visibility benefit of controls
                                                             Baseline       impact (dv)     over baseline (dv) maximum    over baseline (dv) average top
                      Class I area                          impact (dv)    (average top               impact                     ten impacted days
                                                             (maximum)     ten impacted  ---------------------------------------------------------------
                                                                               days)         DSI \57\          WFGD          DSI \58\          WFGD
--------------------------------------------------------------------------------------------------------------------------------------------------------
Breton..................................................           0.713           0.315           0.187           0.399           0.117           0.271
Caney Creek.............................................           2.051           1.005           0.119           0.238           0.271           0.459
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The CAMx-modeled visibility benefits of WFGD are 0.212 dv at Breton 
and 0.119 dv at Caney Creek over those from DSI for the most impacted 
day. Examining the top ten impacted days during the baseline period, 
the average benefit on this set of days of WFGD over DSI is 0.154 dv at 
Breton and 0.188 dv at Caney Creek. As enhanced DSI would reduce 
SO2 emissions from an emission rate of 0.41 lb/MMBtu to 0.3 
lb/MMBtu, enhanced DSI would lead to greater visibility benefits than 
DSI. Thus, the visibility benefits of WFGD compared to enhanced DSI 
would be smaller than those discussed above.
    As explained in our TSD, we identified some uncertainties with 
Cleco's BART analysis for Rodemacher 2. These include a lack of 
documentation for cost figures, and the fact that the DSI testing that 
Cleco relied on was not intended to evaluate DSI for SO2 
control efficiency, which caused some uncertainty concerning the 
potential control level of DSI and enhanced DSI. However, because DSI 
and a fabric filter baghouse are already installed and operational, the 
cost-effectiveness of Cleco's enhanced DSI is based only on the cost of 
the additional reagent and no additional capital costs are involved. 
Consequently, we believe that the uncertainty of Cleco's enhanced DSI 
cost-effectiveness figures is low and that Cleco's estimated cost-
effectiveness of $967/ton \59\ is reasonable. Conversely, we believe 
that significant uncertainty exists with respect to Cleco's cost-
effectiveness estimates for SDA and wet FGD--$8,589/ton and $5,580/ton, 
respectively. Based on our experience reviewing and conducting control 
cost analyses for many other facilities, we believe that Cleco's 
estimates are likely too high.
---------------------------------------------------------------------------

    \59\ Cleco lists this as an incremental cost-effectiveness 
figure for enhanced DSI over the existing DSI system. However, the 
enhanced DSI system has no additional capital costs, and when the 
already sunk capital costs of the existing DSI system are removed 
(which have been carried forward), the $967/ton figure becomes the 
average cost-effectiveness value for enhanced DSI.
---------------------------------------------------------------------------

    Nevertheless, even though the actual costs of SDA and wet FGD are 
likely lower, enhanced DSI is more cost-effective and the incremental 
costs of obtaining the additional 0.1-0.2 dv of visibility improvement 
that can be achieved by SDA or wet FGD are likely to be high. 
Therefore, we propose to agree with Louisiana's determination that 
enhanced DSI is SO2 BART for Rodemacher 2, with a 
SO2 emission limit of 0.30 lbs/MMBtu on a 30-day rolling 
basis. LDEQ and Cleco entered into an AOC to make this limit 
enforceable.
    In assessing PM BART, Cleco notes that Rodemacher 2 is equipped 
with an electrostatic precipitator (ESP) and a fabric filter baghouse, 
which offer excellent PM control, and concludes that PM BART is no 
further control. As discussed earlier, the BART rules allow for a more 
streamlined approach to making BART determinations when 
appropriate.\60\ The BART Guidelines further state that if a BART 
source

[[Page 22946]]

already has controls that are among the most stringent available and 
the controls are made federally enforceable for BART, the remainder of 
the BART analysis is unnecessary.\61\ The existing ESP combined with 
the baghouse meets the definition of ``among the most stringent 
controls'' for PM at this unit and are made federally enforceable for 
BART through the AOC. The AOC allows the unit to meet the emissions 
limits by use of the ESP and the baghouse, conversion to natural gas 
only, unit retirement, or another means of achieving compliance.
---------------------------------------------------------------------------

    \60\ 70 FR 39116.
    \61\ 40 CFR 51 Appendix Y.IV.D.1.9.
---------------------------------------------------------------------------

    In addition, CALPUFF visibility modeling shows that baseline 
impairment due to PM is very small, at 0.01 dv or less at both Breton 
and Caney Creek compared to the overall visibility impairment from all 
pollutants of approximately 0.6 dv.\62\ Our CAMx modeling estimates 
that baseline visibility impairment due to PM emissions from the unit 
is less than 1% of the total visibility impairment due to the unit, at 
both Caney Creek and Breton.\63\ We propose to find that the visibility 
impacts due to PM emissions are so minimal that any additional PM 
controls would only result in very minimal visibility benefit that 
could not justify the cost of any upgrades and/or operational changes 
needed to achieve a more stringent emission limit. We therefore propose 
to agree with Louisiana that no additional controls are required to 
satisfy PM BART. LDEQ and Cleco entered into an AOC establishing an 
enforceable limit on PM10 consistent with current controls 
at 545 lb/hr on a 30-day rolling basis.
---------------------------------------------------------------------------

    \62\ See Table 4-3 CLECO Brame Energy Center BART Five-Factor 
Analysis, prepared by Trinity Consultants, October 31, 2015. 
Available in Appendix B of the 2017 Regional Haze SIP submittal.
    \63\ Calculated as percent of total extinction due to the unit. 
See CAMx Modeling TSD for additional information.
---------------------------------------------------------------------------

b. Entergy Little Gypsy
    Entergy operates three BART-eligible units at Little Gypsy 
Generating Plant (Little Gypsy). Unit 2 is an EGU boiler with a maximum 
heat input capacity of 4,550 MMBtu/hr that is permitted to burn natural 
gas as its primary fuel, and No. 2 and No. 4 fuel oil as secondary 
fuels. Unit 3 is an EGU boiler with a maximum heat input capacity of 
5,578 MMBtu/hr that burns natural gas, but is also permitted to burn 
fuel oil. The auxiliary boiler for Unit 3 has a maximum heat input 
capacity of 252 MMBtu/hr and is permitted to burn only natural gas. 
According to November 9, 2015 updated CALPUFF screening modeling 
conducted by Trinity Consultants on behalf of Entergy,\64\ the baseline 
visibility impacts of Little Gypsy are greater than 0.5 dv, so the 2017 
SIP revision demonstrates that the three units at Little Gypsy are 
subject to BART.\65\
---------------------------------------------------------------------------

    \64\ See Appendix D of the 2017 SIP submittal.
    \65\ See CALPUFF Modeling TSD for a summary of model results.
---------------------------------------------------------------------------

    LDEQ and Entergy entered into an AOC limiting fuel oil to ultra-low 
sulfur diesel (ULSD) with a sulfur content of 0.0015% for both Units 2 
and 3. As the BART Guidelines state, ``if a source commits to a BART 
determination that consists of the most stringent controls available, 
then there is no need to complete the remaining analyses.'' \66\ 
Entergy states that during the baseline period, Units 2 and 3 burned 
fuel oil \67\ with an average sulfur content of 0.5%. Switching to ULSD 
will result in a reduction of SO2 emissions of over 99%. We 
propose to find that ULSD is the most stringent control available for 
addressing SO2 emissions from fuel oil burning, and we 
propose to agree with LDEQ that this satisfies BART for SO2 
for Little Gypsy Unit 2.
---------------------------------------------------------------------------

    \66\ See 40 CFR part 51, Appendix Y, IV, D.
    \67\ For this and all units herein assessed for BART, the 
primary fuel burned has historically been pipeline quality natural 
gas. Please see the TSD for more details.
---------------------------------------------------------------------------

    The 2017 Louisiana Regional Haze SIP narrative does not include a 
BART determination for the auxiliary boiler, but the BART analysis in 
Appendix D of the SIP submittal does address the auxiliary boiler and 
concludes that no additional controls are necessary for BART. The 
auxiliary boiler is permitted to only burn natural gas. We note that 
SO2 and PM emissions for gas-fired units are inherently low 
\68\ and so minimal that the installation of any additional PM or 
SO2 controls on such units would likely achieve very low 
emissions reductions and minimal visibility benefits. As there are no 
appropriate add-on controls and the status quo reflects the most 
stringent controls, we propose to agree with LDEQ that SO2 
and PM BART is no additional controls for the Little Gypsy auxiliary 
boiler. For the same reason, we propose to approve LDEQ's conclusion 
that PM BART for Little Gypsy Units 2 and 3 during gas-firing operation 
is no additional controls.
---------------------------------------------------------------------------

    \68\ AP 42, Fifth Edition, Volume 1, Chapter 1: External 
Sources, Section 1.4, Natural Gas Combustion, available here: 
https://www3.epa.gov/ttn/chief/ap42/ch01/final/c01s04.pdf.
---------------------------------------------------------------------------

    With regards to PM BART for the fuel-oil-firing scenarios at Units 
2 and 3, Louisiana evaluated wet ESP, wet scrubber, cyclone, and 
switching fuels to 0.0015% S fuel oil (ULSD). In evaluating energy and 
non-air quality impacts, the BART analysis identifies energy impacts 
associated with energy usage for ESPs and scrubbers. In addition, ESPs 
and scrubbers generate wastewater streams and the resulting wastewater 
treatment will generate filter cake, requiring land-filling. LDEQ did 
not identify any impacts regarding remaining useful life. The costs of 
compliance for these add-on control options are very high compared to 
their anticipated visibility benefits.\69\ The modeled visibility 
benefits of add-on controls are very small and range from 0.0 dv to 
0.037 dv for cyclone, wet scrubber, and wet ESP. Therefore, we propose 
that the costs of add-on PM controls do not justify the expected 
improvement in visibility. Accordingly, we are proposing to agree with 
Louisiana that the fuel sulfur content limits contained in the AOC that 
were determined to meet SO2 BART also satisfy PM BART.
---------------------------------------------------------------------------

    \69\ See TSD for summary of PM control cost analysis.
---------------------------------------------------------------------------

c. Entergy Ninemile Point
    Entergy operates two BART-eligible units at Ninemile Point Electric 
Generating Plant (Ninemile Point). Unit 4 is an EGU boiler with a 
maximum heat input capacity of 7,146 MMBtu/hr that burns primarily 
natural gas and No. 2 and No. 4 fuel oil. Unit 5 is an EGU boiler with 
a maximum heat input capacity of 7,152 MMBtu/hr that burns primarily 
natural gas and No. 2 and No. 4 fuel oil. LDEQ's SIP submittal 
demonstrates that the two units at Ninemile Point are subject to BART. 
LDEQ and Entergy entered into an AOC limiting fuel oil to ULSD with a 
sulfur content of 0.0015%. As the BART Guidelines state ``if a source 
commits to a BART determination that consists of the most stringent 
controls available, then there is no need to complete the remaining 
analyses.'' \70\ Entergy states that during the baseline period these 
units burned fuel oil with an average sulfur content of 0.3%. Switching 
to ULSD will result in a reduction of SO2 emissions by over 
99%. We propose to find that ULSD is the most stringent control 
available for addressing SO2 emissions and we propose to 
agree with LDEQ that this satisfies BART for SO2 for 
Ninemile Point Units 4 and 5.
---------------------------------------------------------------------------

    \70\ See 40 CFR part 51, Appendix Y, IV, D.
---------------------------------------------------------------------------

    For PM BART for Units 4 and 5, Louisiana evaluated wet ESP, wet 
scrubber, cyclones, and switching fuels to ULSD. In evaluating energy 
and non-air quality impacts, the BART analysis identifies energy 
impacts associated with energy usage for ESPs and scrubbers. In 
addition, ESPs and

[[Page 22947]]

scrubbers generate wastewater streams and the resulting wastewater 
treatment will generate filter cake, requiring land-filling. LDEQ did 
not identify any impacts regarding the remaining useful life. The cost 
of compliance for these add-on control options is very high compared to 
the anticipated visibility benefits of controls. The modeled visibility 
benefits of add-on controls are very small and range from 0 dv to 0.08 
dv for cyclone, wet scrubber and wet ESP. The BART analyses in the 2017 
Louisiana Regional Haze SIP demonstrate that the cost of retrofitting 
the Units 4 and 5 with add-on PM controls would be extremely high 
compared to the visibility benefit for any of the units.\71\ We believe 
that the cost of add-on PM controls does not justify the minimal 
expected improvement in visibility for these units. Accordingly, we are 
proposing to agree with LDEQ's determination that the fuel content 
limits for oil burning contained in the AOC that were determined to 
meet SO2 BART also satisfy PM BART for Units 4 and 5.
---------------------------------------------------------------------------

    \71\ See TSD for summary of PM control cost analysis.
---------------------------------------------------------------------------

d. Entergy Waterford
    Entergy operates three BART-eligible units at the Waterford 1 & 2 
\72\ Generating Plant (Waterford) in St. Charles Parish, Louisiana. 
Unit 1 is an EGU boiler with a maximum heat input capacity of 4,440 
MMBtu/hr that burns primarily natural gas and No. 6 fuel oil as its 
secondary fuel. Unit 2 is an EGU boiler with a maximum heat input 
capacity of 4,440 MMBtu/hr that burns primarily natural gas and No. 6 
fuel oil as its secondary fuel. The auxiliary boiler (77 MMBtu/hr) 
burns only natural gas. We propose to approve the determination that 
Waterford Units 1 and 2, and the auxiliary boiler are subject to BART. 
In assessing SO2 BART for Units 1 and 2, Louisiana 
considered the five BART factors.
---------------------------------------------------------------------------

    \72\ Note that the name of this facility is ``Waterford 1 & 2'' 
and is also has units that are referred to as ``Unit 1'' and ``Unit 
2''.
---------------------------------------------------------------------------

    In Step 1, SO2 control technologies of DSI, SDA, wet 
scrubbing, and fuel switching were identified as available controls. 
For gas-fired units that occasionally burn fuel oil, the BART 
Guidelines recommend: ``For oil-fired units, regardless of size, you 
should evaluate limiting the sulfur content of the fuel oil burned to 1 
percent or less by weight.'' \73\ The Waterford units have only burned 
residual fuel oil (No. 6). Entergy states that these units are only 
physically capable of burning No. 6 fuel oil when not burning natural 
gas and evaluated switching to 0.5% sulfur No. 6 fuel oil, the lowest 
sulfur specification No. 6 fuel oil available.
---------------------------------------------------------------------------

    \73\ 70 FR 39103, 39171 (July 6, 2005) [40 CFR 51, App. Y].
---------------------------------------------------------------------------

    In Step 2, Louisiana eliminated all controls as technically 
infeasible with the exception of fuel switching. We are aware, however, 
of instances, although not at any facility in the U.S., in which FGDs 
of various types have been installed or otherwise deemed feasible on a 
boiler that burns oil.\74\ Consequently, we have supplemented 
Louisiana's analysis with our own. We propose from our analysis, that 
even if the LDEQ included analyses of these other control options, the 
State's BART conclusion for Waterford would still be reasonable.\75\
---------------------------------------------------------------------------

    \74\ Crespi, M. ``Design of the FLOWPAC WFGD System for the 
Amager Power Plant.'' Power-Gen FGD Operating Experience, November 
29, 2006, Orlando, FL; Babcock and Wilcox. ``Wet Flue Gas 
Desulfurization (FGD) Systems Advanced Multi-Pollutant Control 
Technology.'' See Page 4: ``We have also provided systems for heavy 
oil and Orimulsion fuels.'' DePriest, W; Gaikwad, R. ``Economics of 
Lime and Limestone for Control of Sulfur Dioxide.'' See page 7: ``A 
CFB unit, in Austria, is on a 275 MW size oil-fired boiler burning 
1.0-2.0% sulfur oil.''
    \75\ See the TSD for our analysis of these other control 
options. We believe that the installation of any of these other add-
on control options, such as a scrubber, on any of these gas-fired 
units that occasionally burn oil results in very high cost-
effectiveness values.
---------------------------------------------------------------------------

    In addition, Louisiana evaluated switching from a 1% sulfur fuel 
oil, which is approximately equal to the maximum sulfur content of the 
fuel oil these units have burned, to a 0.5% sulfur fuel oil for Units 1 
and 2. In addition to the Entergy BART report which Louisiana relied 
upon, we have included our own fuel oil cost assessment in the TSD.
    For Step 3, the technically feasible controls are ranked by control 
effectiveness. The control effectiveness of switching from a higher 
sulfur fuel oil to a lower sulfur fuel oil depends on the reduction in 
sulfur emissions. Entergy states that these units are only physically 
capable of burning No. 6 fuel oil when not burning natural gas and 
evaluated switching to 0.5% sulfur No. 6 fuel oil, the lowest sulfur 
specification No. 6 fuel oil available. We believe it is likely the 
units could be modified to burn distillate fuel oils, with even lower 
sulfur content, at low cost. We welcome the facility owner, Entergy, to 
provide a cost estimate for the modification to burn distillate fuel 
oils should it have concerns with this assumption.
    Because we believe it likely that the facility could be modified to 
burn distillate fuels at low cost, in addition to our consideration of 
0.5% No. 6 fuel oil, we also considered No. 2 fuel oils with 0.3% 
sulfur and ultra-low sulfur diesel, which has a sulfur content of 
0.0015%.
    In evaluating energy and non-air quality impacts, the BART analysis 
in the 2017 SIP submittal states that there are no such impacts 
associated with fuel switching. It also states that remaining useful 
life does not impact the BART analysis. We believe Louisiana's 
assessment of the impacts from fuel switching are reasonable.
    Aside from our conclusion that modifications necessary to burn 
distillate fuel oil are relatively minor, the cost-effectiveness of 
fuel oil switching depends only on the cost of the lower sulfur fuel 
oil relative to the baseline fuel oil. Information from the Energy 
Information Agency (EIA) indicates that fuel oil of varying sulfur 
contents is widely available across the U.S. EIA reports the prices for 
various refinery petroleum products on a monthly and annual basis. See 
the TSD for additional information on fuel oil prices utilized in our 
analysis. In Table 9, we present the results of our calculations: \76\
---------------------------------------------------------------------------

    \76\ See the file, ``LA BART Fuel Oil Cost Analysis.xlsx'' for 
the calculations and supporting data for these figures.

              Table 9--Control Cost Analysis for Fuel Oil Switching From Residual Fuel Oil Baseline
----------------------------------------------------------------------------------------------------------------
                                        Baseline: Residual Fuel Oil <=1%
-----------------------------------------------------------------------------------------------------------------
                                                                                   Tons reduced        Cost
                                                                  Cost for 1,000     per 1,000     effectiveness
                                                                  barrels ($/yr)      barrels         ($/ton)
----------------------------------------------------------------------------------------------------------------
Business as usual (Residual fuel oil @1% S and $0.971/gal)......         $40,782
Moderate control (No. 2 fuel oil @0.3% S and $1.565/gal)........          65,730            2.40         $10,385
High control (ULSD @0.0015% S and $1.667/gal)...................          70,014            3.29           8,878
----------------------------------------------------------------------------------------------------------------


[[Page 22948]]

    In assessing the visibility benefits of fuel switching, Louisiana 
submitted CALPUFF modeling for 1% sulfur and 0.5% sulfur fuel oil. We 
performed additional CALPUFF modeling to correct for errors in the 
modeling and to evaluate the visibility benefits of additional fuel 
types. See the CALPUFF Modeling TSD for additional information on 
modeling inputs and results. The visibility benefits from fuel 
switching are summarized in Table 10.

                          Table 10--Visibility Benefits of Fuel Switching at Waterford
                                           [CALPUFF, 98th percentile]
----------------------------------------------------------------------------------------------------------------
                                                                    Visibility      Visibility      Visibility
                                  Class I area       Baseline      benefit (dv)    benefit (dv)    benefit (dv)
                                                    impact (dv)      of 0.5% S       of 0.3% S     of 0.0015% S
----------------------------------------------------------------------------------------------------------------
Unit 1........................  Breton..........           2.704           0.883           1.348           1.744
Unit 2........................  Breton..........           2.378           0.798           1.207           1.601
----------------------------------------------------------------------------------------------------------------

    The cost-effectiveness of switching to a lower sulfur fuel oil is 
less attractive (higher $/ton) than other controls we have typically 
required under BART. While the visibility benefits of switching fuel 
types are significant, the cost-effectiveness in terms of $/ton is in 
excess of $8,000/ton for the most stringent control option. We also 
note that the facility primarily operates by burning natural gas and 
the visibility benefits presented in Table 10 represent benefits only 
for those periods when fuel oil is burned and would not occur during 
natural gas operation. As discussed above, over the 2011-2015 period, 
the highest annual emissions for SO2 reported for a unit at 
the facility is only 69 tons/year. Considering this, we propose to 
agree with the LDEQ's determination that no additional controls or fuel 
switching are necessary to satisfy BART. The LDEQ and Entergy have 
entered into an AOC limiting fuel oil sulfur content to 1% or less. 
This enforceable limit is consistent with past practice, the baseline 
level utilized in the BART analysis, and the minimum recommendation in 
the BART Guidelines. We encourage Louisiana and Entergy to reconsider 
switching to a lower sulfur fuel when assessing controls under 
reasonable progress for future planning periods.
    For PM BART for Units 1 and 2, Louisiana evaluated wet ESP, wet 
scrubber, cyclones, and switching fuels to 0.5% S fuel oil. In 
evaluating energy and non-air quality impacts, Louisiana identified 
energy impacts associated with energy usage for ESPs and scrubbers. In 
addition, ESPs and scrubbers generate wastewater streams and the 
resulting wastewater treatment will generate filter cake, requiring 
land-filling. Louisiana did not identify any impacts regarding 
remaining useful life. The costs of compliance for these control 
options are very high compared to their anticipated visibility 
benefits. Modeled baseline visibility impacts from PM emissions are 
very low. Modeled visibility impairment from baseline PM emissions are 
less than 5% of the total modeled impact from the source. Entergy's 
modeled visibility benefits of add-on controls are very small and range 
from 0 dv to 0.06 dv for cyclone, wet scrubber, and wet ESP for each 
unit. The BART analyses in the 2017 Louisiana Regional Haze SIP 
demonstrate that the cost of retrofitting Units 1 and 2 with add-on PM 
controls would be extremely high compared to the visibility benefits 
for any of the units.\77\ LDEQ concluded that the costs of add-on PM 
controls do not justify the minimal expected improvement in visibility 
for these units. LDEQ included an analysis of fuel switching for PM 
BART in its SO2 BART analysis, as PM reductions from fuel 
switching were also included in the assessment of benefits from fuel 
switching. Accordingly, we are proposing to agree with the 
determination in the 2017 Louisiana Regional Haze SIP that the fuel 
content limits for oil burning contained in the AOC that were 
determined to meet SO2 BART also satisfy PM BART.
---------------------------------------------------------------------------

    \77\ See TSD for summary of PM control cost analysis.
---------------------------------------------------------------------------

    The 2017 Louisiana Regional Haze SIP narrative does not include a 
BART determination for the auxiliary boiler, but the BART analysis in 
Appendix D of the 2017 SIP submittal does address the auxiliary boiler 
and concludes that no additional controls are necessary for BART. The 
auxiliary boiler only burns natural gas. We note that SO2 
and PM emissions for gas-only units are inherently low,\78\ so the 
installation of any additional PM or SO2 controls on such 
units would likely achieve very low emissions reductions and minimal 
visibility benefits. As there are no appropriate add-on controls, and 
the status quo reflects the most stringent controls, we propose to 
agree with Louisiana that SO2 and PM BART is no additional 
controls for the Waterford auxiliary boiler.
---------------------------------------------------------------------------

    \78\ AP 42, Fifth Edition, Volume 1, Chapter 1: External 
Sources, Section 1.4, Natural Gas Combustion, available here: 
https://www3.epa.gov/ttn/chief/ap42/ch01/final/c01s04.pdf.
---------------------------------------------------------------------------

III. Proposed Action

    We are proposing to approve Louisiana's Regional Haze SIP revision 
submitted on February 10, 2017, with the exception of the portion 
related to the Entergy Nelson facility. We propose to approve the BART 
determination for Michoud based on the draft permit, and note that we 
expect the proposed permit removing Units 2 and 3 to be final before we 
take final action to approve this portion of the 2017 Louisiana 
Regional Haze SIP. Alternatively, LDEQ could submit another enforceable 
document to ensure that Units 2 and 3 cannot restart without a BART 
analysis and emission limits, or demonstrate the units have been 
deconstructed to the point that they cannot restart without obtaining a 
new NSR permit, making them not operational during the timeframe for 
BART eligibility. Additionally, final approval of Louisiana's reliance 
on CSAPR to satisfy NOX BART for EGUs is contingent upon our 
finalization of the separate rulemaking, proposed on November 10, 2016 
(81 FR 78954), that proposed to find that CSAPR continues to be better 
than BART. Once we take final action on our proposed approval of 
Louisiana's 2016 SIP revision addressing non-EGU BART,\79\ this 
proposal, and a future proposed action to address SO2 and PM 
BART for the Entergy Nelson facility, we will have fulfilled all 
outstanding obligations with respect to the Louisiana regional haze 
program for the first planning period.
---------------------------------------------------------------------------

    \79\ 81 FR 74750 (October 27, 2016).
---------------------------------------------------------------------------

IV. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, the

[[Page 22949]]

EPA's role is to approve state choices, provided that they meet the 
criteria of the CAA. Accordingly, this action merely proposes to 
approve state law as meeting Federal requirements and does not impose 
additional requirements beyond those imposed by state law. For that 
reason, this action:

     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 
21, 2011);
     Does not impose an information collection burden under 
the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et 
seq.);
     Is certified as not having a significant economic 
impact on a substantial number of small entities under the 
Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly 
or uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action 
based on health or safety risks subject to Executive Order 13045 (62 
FR 19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 
272 note) because it does not involve technical standards; and
     Does not provide EPA with the discretionary authority 
to address, as appropriate, disproportionate human health or 
environmental effects, using practicable and legally permissible 
methods, under Executive Order 12898 (59 FR 7629, February 16, 
1994).

In addition, the SIP is not approved to apply on any Indian reservation 
land or in any other area where EPA or an Indian tribe has demonstrated 
that a tribe has jurisdiction. In those areas of Indian country, the 
proposed rule does not have tribal implications and will not impose 
substantial direct costs on tribal governments or preempt tribal law as 
specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Nitrogen dioxide, Ozone, 
Particulate matter, Reporting and recordkeeping requirements, Sulfur 
dioxides, Visibility, Interstate transport of pollution, Regional haze, 
Best available control technology.

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

    Dated: May 1, 2017.
Samuel Coleman,
Acting Regional Administrator, Region 6.
[FR Doc. 2017-10108 Filed 5-18-17; 8:45 am]
BILLING CODE 6560-50-P