Court Opinion

ID: 9964461
Source: CourtListenerOpinion
Date Created: 2024-04-30 00:00:41.040137+00
Date Added: 2024-06-11T08:25:31.052647
License: Public Domain

Case: 23-60234      Document: 142-1         Page: 1   Date Filed: 04/29/2024

        United States Court of Appeals
             for the Fifth Circuit
                            ____________                       United States Court of Appeals
                                                                        Fifth Circuit

                             No. 23-60234
                                                                      FILED
                                                                  April 29, 2024
                            ____________
                                                                 Lyle W. Cayce
Sierra Club,                                                          Clerk

                                                                   Petitioner,

                                   versus

Louisiana Department of Environmental Quality;
Roger W. Gingles, in his official capacity as Secretary, Louisiana
Department of Environmental Quality,

                                                                Respondents.
               ______________________________

      Petition for Review of an Order of the Civil Aeronautics Board
                Agency Nos. 0560-00997-V0, PSD-LA-841
               ______________________________

Before Stewart, Duncan, and Engelhardt, Circuit Judges.
Kurt D. Engelhardt, Circuit Judge:
      This case involves a challenge to the pre-construction permits issued
by the Louisiana Department of Environmental Quality (“LDEQ”) to
Commonwealth LNG, LLC (“Commonwealth”) for its planned liquefied
natural gas (“LNG”) export facility in Cameron Parish, Louisiana.
Petitioner Sierra Club asks this Court to vacate LDEQ’s permitting decision
as arbitrary and contrary to law, arguing that the facility’s emissions will
exceed National Ambient Air Quality Standards (“NAAQS”) and that
LDEQ failed to require Commonwealth to use the best available control
Case: 23-60234         Document: 142-1          Page: 2      Date Filed: 04/29/2024

technology (“BACT”) to limit those emissions. For the following reasons,
we DENY Sierra Club’s petition for review and affirm LDEQ’s permitting
decision.
            I.   Factual and Regulatory Background
        Commonwealth, an LNG 1 development company, plans to build an
LNG liquefaction and export facility in Cameron Parish, Louisiana, on the
west bank of the Calcasieu Ship Channel at the Gulf of Mexico. Before
beginning construction on its project, Commonwealth must obtain various
federal, 2 state, and local authorizations. At issue here are authorizations
issued by LDEQ following an analysis of the facility’s projected air
emissions.
        Commonwealth’s facility is projected to produce air emissions
regulated by the Clean Air Act (“CAA”), which “establishes a
comprehensive program for controlling and improving the nation’s air
quality through state and federal regulation.” BCCA Appeal Grp. v. U.S.
E.P.A., 355 F.3d 817, 821–22 (5th Cir. 2003), as amended on denial of reh’g and
reh’g en banc (Jan. 8, 2004); 42 U.S.C. § 7401 et seq. Under the CAA, the
States work in concert with the Environmental Protection Agency (“EPA”)
to regulate air pollution emissions from stationary sources—the CAA thus
operates as “[a]n experiment in cooperative federalism.” Luminant
Generation Co. v. U.S. E.P.A., 675 F.3d 917, 921 (5th Cir. 2012) (citation

        _____________________
        1
          Liquified natural gas is natural gas that has been cooled to a liquid state for
shipping and storage purposes.
        2
          On August 20, 2019, Commonwealth filed its application for approval of the
proposed facility with the Federal Energy Regulatory Commission (“FERC”) pursuant to
Section 3(a) of the Natural Gas Act. On September 9, 2022, FERC issued its extensive
review of the proposed LNG project, and on November 17, 2022, FERC issued a final
order approving the project. Sierra Club does not challenge FERC’s order in this appeal.
Case: 23-60234      Document: 142-1       Page: 3    Date Filed: 04/29/2024

omitted). This regulatory scheme is relatively simple: the EPA establishes
NAAQS for specific air pollutants, and the States are responsible for
implementing those standards. Id.; see 42 U.S.C. § 7407(a) (“Each State shall
have the primary responsibility for assuring air quality within the entire
geographic area comprising such State.”).
       The NAAQS program requires the EPA to identify air pollutants
that “may reasonably be anticipated to endanger public health or welfare.”
42 U.S.C. § 7408(a)(1)(A). Then, the “EPA identif[ies] the maximum
airborne concentration of a pollutant that the public health can tolerate,
decrease[s] the concentration to provide an ‘adequate’ margin of safety, and
set[s] the standard at that level.” Whitman v. Am. Trucking Ass’ns, 531 U.S.
457, 465 (2001). There are currently NAAQS for six pollutants: carbon
monoxide (“CO”), lead, nitrogen dioxide (“NO2”), ozone, particulate
matter (“PM10/PM2.5”), and sulfur dioxide (“SO2”). See generally 40 C.F.R.
§§ 50.4–19.
       To ensure air quality within its borders satisfies the NAAQS, a State
must “submit[] an implementation plan . . . which will specify the manner in
which national primary and secondary ambient air quality standards will be
achieved and maintained.” 42 U.S.C. § 7407(a). The EPA is then “required
to approve each State’s plan” if it is satisfied the State Implementation Plan
(“SIP”) meets the CAA’s general conditions. Train v. Nat. Res. Def.
Council, Inc., 421 U.S. 60, 66 (1975); 42 U.S.C. § 7410(k)(3). The EPA has
approved Louisiana’s SIP. See 40 C.F.R. § 52.970(c).
       To certify that potential new sources of pollution do not erode air
quality, each State’s SIP “must include permitting programs for the
construction or modification of stationary sources.” Luminant Generation
Co., 675 F.3d at 922. Such permit programs are termed “New Source
Review” programs. Id. For “attainment areas,” or areas where the air quality
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is currently compliant with NAAQS, the permitting process is called the
Prevention of Significant Deterioration (“PSD”) program. See generally
LAC 33:III:509. “The PSD requirements, enacted as part of 1977
amendments to the [CAA], are designed to ensure that the air quality in
attainment areas or areas that are already clean will not degrade.” Alaska
Dep’t of Env’t Conservation v. E.P.A., 540 U.S. 461, 470 (2004) (internal
citations and quotations omitted).
        The PSD program requires new sources to obtain a specific
preconstruction permit. 42 U.S.C. § 7475. To receive the permit, the owner
or operator of the proposed facility must demonstrate “that emissions from
construction or operation of such facility will not cause, or contribute to, air
pollution in excess of” the NAAQS. Id. at § 7475(a)(3). The owner or
operator must also show that “the proposed facility is subject to the best
available control technology for each pollutant subject to regulation.” Id. at
§ 7475(a)(4). In Louisiana, LDEQ conducts the PSD permitting process
pursuant to Louisiana’s SIP. 3 See generally LAC 33:III:509. Before issuing a
preconstruction permit, LDEQ must also provide public notice and an
opportunity to comment on the permit. See 40 C.F.R. § 51.161(a).
        In addition to the PSD permitting requirements, Congress also
requires that each State adopt a Title V operating permit program, whose
minimum requirements are set by the EPA. See generally LAC 33.III.507.B.
“Title V’s purpose is to provide each source a single permit that contains
and consolidates all the information it needs to comply with the [CAA].”
Env’t Integrity Project v. U.S. Env’t Prot. Agency, 969 F.3d 529, 536 (5th Cir.

        _____________________
        3
          LDEQ serves as the legislatively-created agency “vested with jurisdiction over
matters affecting the regulation of the environment” in Louisiana, “including, but not
limited to, the regulation of air quality.” St. James v. La. Dep’t of Env’t Quality, 2023-0578,
2024 WL 207859, at *2 (La. App. 1 Cir. 1/19/24), reh’g denied (Feb. 15, 2024).
Case: 23-60234       Document: 142-1       Page: 5     Date Filed: 04/29/2024

2020). The EPA has approved Louisiana’s Title V permitting program. See
60 Fed. Reg. 47296-01.
       On April 23, 2021, Commonwealth applied for the required PSD and
Title V permits for its proposed LNG facility. LDEQ then began its two-
year review of the permit application. In February 2022, LDEQ issued a
notice inviting public comment on the proposed project. Thereafter, on
March 28, 2023, LDEQ issued the two permits to Commonwealth, along
with its Basis for Decision and its Public Comments Response Summary. On
April 27, 2023, Sierra Club timely filed this petition for review challenging
the permitting decision.
        II.   Standard of Review
       There is an apparent circuit split as to the appropriate standard of
review for state agency actions. One view is that “[f]ederal courts reviewing
state agency action afford the agencies the deference they would receive
under state law.” Twp. of Bordentown v. FERC, 903 F.3d 234, 270 (3d Cir.
2018). Both LDEQ and Commonwealth advocate for this standard of
review. The other view is that the federal Administrative Procedure Act’s
(“APA”) arbitrary and capricious review applies. See Appalachian Voices v.
State Water Control Bd., 912 F.3d 746, 753 (4th Cir. 2019) (reviewing
Virginia’s certification under the APA’s standards).
       We agree with the Third Circuit and others that have adopted the first
view, primarily because “the federal APA by its terms does not apply to
states.” Town of Weymouth v. Mass. Dep’t of Env’t Prot., 961 F.3d 34, 41 (1st
Cir.), on reh’g, 973 F.3d 143 (1st Cir. 2020); see 5 U.S.C.A. § 551(1). Further,
a recent decision by this Court applied Texas state law, rather than the APA
standard, to review a Texas environmental agency’s permitting decision. See
Port Arthur Cmty. Action Network v. Tex. Comm’n on Env’t Quality, 86 F.4th
653 (5th Cir. 2023), opinion withdrawn and superseded on denial of reh’g, No.
Case: 23-60234         Document: 142-1         Page: 6      Date Filed: 04/29/2024

22-60556, 2024 WL 655983 (5th Cir. Feb. 16, 2024) (noting the parties’
agreement that the Court “should apply the standard of review that would
apply to [the agency] in Texas state courts”). Thus, we apply Louisiana law
to review LDEQ’s permitting decision here. 4
       Under Louisiana law, a court “may reverse or modify” a state
agency’s “decision if substantial rights of the appellant have been prejudiced
because the administrative findings, inferences, conclusions, or decisions are
. . . [a]rbitrary or capricious or characterized by abuse of discretion or clearly
unwarranted exercise of discretion.” La. R.S. § 49:978.1(G)(5). “The test for
determining whether an action was arbitrary or capricious is whether the
action taken was ‘without reason.’” Save Our Hills v. La. Dep’t of Env’t
Quality, 266 So.3d 916, 927 (La. App. 1 Cir. 11/5/18), writ denied, 267 So.3d
87 (La. 3/18/19) (quoting Dow Chemical Co. La. Operations Complex Cellulose
and Light Hydrocarbons Plants, Part 70 Air Permit Major Modifications and
Emission v. Reduction Credits, 885 So.2d 5, 10 (La. App. 1 Cir. 9/17/04)).
       “Reviewing courts should not reverse a substantive decision on its
merits, unless it be shown that the actual balance of costs and benefits that
was struck was arbitrary or clearly gave insufficient weight to environmental
protection.” Save Ourselves, Inc. v. La. Env’t Control Comm’n, 452 So.2d
1152, 1159 (La. 1984). “However, if the decision was reached procedurally,
without individualized consideration and balancing of environmental factors
conducted fairly and in good faith, it is the courts’ responsibility to reverse.”
Id. “[T]he agency is required to make basic findings supported by evidence
and ultimate findings which flow rationally from the basic findings; and it
must articulate a rational connection between the facts found and the order

       _____________________
        4
           Regardless, because Louisiana’s law concerning agency review is substantially
similar to the APA’s standard of review, both likely lead to the same result here.
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issued.” Id. “Although we may uphold a decision of less than ideal clarity if
the agency’s path may reasonably be discerned, . . . we will not supply a
finding from the evidence or a reasoned basis for the commission’s action
that the commission has not found or given.” Id. at 1160.
       III.     Analysis
       Sierra Club, both during the public comment period and now on
appeal, argues that LDEQ acted arbitrarily in its analysis of the potential
NAAQS violations from the Commonwealth facility. Specifically, Sierra
Club believes that LDEQ’s use of significant impact levels (“SILs”)
throughout the emissions analysis was improper. Sierra Club further asserts
that LDEQ compounded its error by relying on AP-42 emission factors,
“despite EPA’s caution against doing so.” Separately, Sierra Club argues
that LDEQ failed to require BACT from Commonwealth with respect to
NOx emissions from Commonwealth’s planned combustion turbines and
oxidation system. Finally, Sierra Club asserts that LDEQ violated its public
trustee duty under Louisiana law, which requires LDEQ “to evaluate and
avoid adverse environmental impacts to the maximum extent possible.” In
response, in addition to contesting each of these arguments, LDEQ
challenges this Court’s jurisdiction to hear Sierra Club’s claim.
           a. Whether this Court has subject matter jurisdiction.
       LDEQ challenges this Court’s jurisdiction over the petition for
review, arguing that Sierra Club’s claim arises under state law, not federal
law, and lacks a sufficient hook to bring the claim into federal court. Both
Sierra Club and Commonwealth, as intervenor, disagree, asserting instead
that the unique interplay between the Natural Gas Act (“NGA”), the CAA,
and the Louisiana SIP provides this Court with exclusive jurisdiction over
the petition.
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       First, the NGA. The NGA is “a comprehensive scheme of federal
regulation” intended to address the sale and transmission of natural gas. N.
Nat. Gas Co. v. State Corp. Comm’n of Kan., 372 U.S. 84, 91 (1963). As such,
“[t]he NGA confers upon FERC [exclusive jurisdiction] over the
transportation and sale of natural gas in interstate commerce for resale.”
Schneidewind v. ANR Pipeline Co., 485 U.S. 293, 300–01 (1988). When
Congress later passed the Energy Policy Act, it extended the reach of the
NGA to the construction, expansion, and operation of LNG terminals, such
as the one at issue here. See 15 U.S.C. § 717b(e)(1). The NGA thus strips
States of the authority to act in this natural gas realm, except under three
specifically enumerated statutes, one of which is the CAA. 15 U.S.C.
§ 717b(d).
       As noted above, the CAA “establishes a comprehensive program for
controlling and improving the nation’s air quality through state and federal
regulation.” BCCA Appeal Grp., 355 F.3d at 821–22. Under the CAA, the
EPA formulates the NAAQS, while “States have primary responsibility for
implementing the NAAQS by developing ‘State implementation plans.’”
Util. Air Regul. Grp. v. E.P.A., 573 U.S. 302, 308 (2014) (quoting 42 U.S.C.
§ 7410). Once the EPA approves a particular State’s SIP, it can then
“delegate to such State any authority . . . to implement and enforce [its]
standards.” 42 U.S.C. § 7411(c)(1). Therefore, when States like Louisiana
conduct a required review under the CAA for the issuance of permits, they
are implementing federal law under a system of cooperative federalism. See,
e.g., Ammex, Inc. v. Wenk, 936 F.3d 355, 361 (6th Cir. 2019) (concluding that
Michigan’s fuel law, made in compliance with EPA’s standards, is federal
law, based on “the way courts have consistently treated SIPs”).
       The fact that SIPs have the force and effect of federal law has been
recognized by every federal circuit court to address the issue, including this
Circuit. See Env’t Tex. Citizen Lobby, Inc. v. ExxonMobil Corp., 968 F.3d 357,
Case: 23-60234       Document: 142-1       Page: 9     Date Filed: 04/29/2024

373 (5th Cir. 2020), as revised, (Aug. 3, 2020), and following remand, 47 F.4th
408 (5th Cir. 2022), and reh’g en banc granted, vacated, 61 F.4th 1012 (5th Cir.
2023) (noting that “when the EPA approves a SIP, it becomes federal
law”); see also, e.g., Grp. Against Smog & Pollution, Inc. v. Shenango Inc., 810
F.3d 116, 120 (3d Cir. 2016) (“Once the EPA approves the SIP, it becomes
binding federal law.”); Indiana v. E.P.A., 796 F.3d 803, 806 (7th Cir. 2015)
(“Once it is approved by EPA, a state rule embodied in a SIP becomes
enforceable federal law.”). We decline to depart from our sister circuits on
this issue. Thus, contrary to LDEQ’s arguments, when LDEQ issued the
permit, it was acting pursuant to federal law, not merely state law.
       Importantly, the NGA vests jurisdiction for judicial review of
permitting decisions in “[t]he United States Court of Appeals for the circuit
in which a facility . . . is proposed to be constructed, expanded, or operated.”
15 U.S.C. § 717r(d)(1). Further, the NGA provides that such circuit court
“shall have original and exclusive jurisdiction over any civil action for the
review of an order or action of a Federal agency . . . or State administrative
agency acting pursuant to Federal law.” Id. (emphasis added). Based on the
clear language of the NGA, and the understanding that LDEQ acted under
federal law in issuing the permits to Commonwealth, we have jurisdiction to
review Sierra Club’s petition. See Town of Weymouth, 961 F.3d at 40–41
(reviewing State agency’s order acting pursuant to the CAA); Friends of
Buckingham v. State Air Pollution Control Bd., 947 F.3d 68, 80 (4th Cir. 2020)
(finding jurisdiction pursuant to the NGA to review the grant of a permit by
the State board).
       This Court recently decided the merits of a CAA challenge to a Texas
Commission on Environmental Quality (“TCEQ”) permitting decision in
Port Arthur Cmty. Action Network, supra. There, a not-for-profit
environmental organization petitioned for review of TCEQ’s decision,
pursuant to the federal CAA and the Texas Clean Air Act, to grant a PSD
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permit to an LNG plant developer. Port Arthur Cmty. Action Network, 86
F.4th at 655–56. 5 This Court, after finding that petitioner had standing to
bring its claim, analyzed TCEQ’s permitting decision under Texas’s
arbitrary and capricious standard, apparently finding no issue with the
Court’s subject matter jurisdiction to hear the case. Id. at 659–60. Consistent
with our previous decisions, we hold that this Court has subject matter
jurisdiction over Sierra Club’s petition, and thus proceed to the merits. 6
            b. Whether LDEQ acted arbitrarily in using SILs to consider the
               Commonwealth permit application.
        Sierra Club first argues, based on the CAA’s clear language, that
neither the EPA nor State agencies may use SILs in permitting decisions.
However, even if the Court finds that SILs are valid under the CAA, Sierra
Club argues that LDEQ used them improperly with respect to NO2
emissions for the Commonwealth LNG project. As noted above, the owner
or operator of a proposed facility must demonstrate “that emissions from
construction or operation of such facility will not cause, or contribute to, air
pollution in excess of” the NAAQS. 42 U.S.C. § 7475(a)(3). Sierra Club
        _____________________
        5
          On February 16, 2024, the panel in the Port Arthur case denied rehearing,
withdrew its previous opinion, and issued a new opinion that certified a question to the
Supreme Court of Texas concerning Texas’s definition of “best available control
technology.” Port Arthur Cmty. Action Network v. Tex. Comm’n on Env’t Quality, No. 22-
60556, 2024 WL 655983, at *2 (5th Cir. Feb. 16, 2024). Because the certified question deals
solely with the interpretation of Texas law, rather than the Court’s ability to review the
permitting decision, the panel’s new opinion does not affect our jurisdiction analysis here.
        6
          LDEQ directs our attention to Shrimpers & Fishermen of RGV v. Tex. Comm’n on
Env’t Quality, 968 F.3d 419, 427 (5th Cir. 2020) (Oldham, J., concurring), in which a
concurring judge suggests that federal courts may lack—or perhaps should lack—
jurisdiction over petitions for review of LNG permits brought under the APA and NGA.
This Court did not decide the jurisdiction issue in Shrimpers & Fishermen because it
concluded that the petitioners did not have standing; therefore, the discussion of
jurisdiction is not controlling here, nor does it persuade us to depart from the reasoning laid
out above.
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argues that Commonwealth’s LNG facility will in fact cause or contribute to
violations of the NAAQS, yet LDEQ issued the preconstruction permits
anyway based on a fundamentally flawed analysis.
                   i.    Whether the use of SILs complies with the CAA.
        Sierra Club argues that LDEQ arbitrarily concluded that
Commonwealth’s facility will not cause or contribute to a NAAQS violation
by conducting a shortened Air Quality Analysis based on SILs. SILs are
numerical values “below which the EPA considers a source to have an
insignificant effect on ambient air quality.” Sierra Club v. E.P.A., 705 F.3d
458, 461 (D.C. Cir. 2013). EPA guidance suggests that when a source
demonstrates that its impact will not exceed the SIL, the source does not
need to conduct the more extensive air quality analysis that is typically
required. See id.; AR75:5. The use of SILs arose out of the EPA’s decades-
long belief that requiring extensive air modeling for every source is costly and
overly burdensome, especially where the source is projected to emit
insignificant amounts of pollution. AR75:5. “In 2010, EPA attempted to
codify these uses of SILs,” but, after recognizing various flaws in the
proposed SILs rule, the EPA asked the D.C. Circuit to vacate the rule. Sierra
Club v. Env’t Prot. Agency, 955 F.3d 56, 59 (D.C. Cir. 2020) 7; see 40 C.F.R.
§ 51.165(b)(2) (allowing for use of SILs to determine if a source would
“exceed the following significance levels”). On remand in that case, the EPA
chose to issue non-binding guidance, rather than a modified rule, explaining

        _____________________
        7
          Notably, Sierra Club asked the D.C. Circuit to hold that the EPA could not use
SILs at all in its air quality modeling. Sierra Club v. E.P.A., 705 F.3d 458, 464 (D.C. Cir.
2013). However, that court declined to do so, instead holding that “[o]n remand the EPA
may promulgate regulations that do not include SILs or do include SILs that do not allow
the construction or modification of a source to evade the requirements of the [CAA].” Id.
Contrary to Sierra Club’s suggestion, the D.C. Circuit has never held that SILs are per se
invalid under the CAA.
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how state permitting authorities—like LDEQ—can rely on SILs in the
PSD permitting process.
       Based on this EPA guidance, LDEQ uses SILs to determine whether
a permit applicant has satisfied “the requirement to demonstrate that they
do not cause or contribute to a violation by showing that the ambient air
quality impacts resulting from the proposed source’s emissions would be
below these concentration levels.” AR75:5; LAC 33:III.509. For any given
permit application, LDEQ conducts a “preliminary screening” whereby it
identifies the projected emissions and compares them to the EPA’s SILs for
each NAAQS. Only for those pollutants that exceed the SIL value does
LDEQ conduct “refined modeling” to further analyze the projected effect
on air quality. AR70:35. In sum, LDEQ uses the SILs as a “compliance
demonstration tool” to simplify the air analysis and “help[] to reduce the
burden on permitting authorities and permit applicants to conduct often
time-consuming and resource-intensive air dispersion modeling” where such
modeling is unnecessary to show compliance with the CAA. AR75:5. For the
Commonwealth facility, LDEQ found that only four of the pollutants
measured above the SILs and thus required refined modeling. AR70:35.
       Sierra Club asserts that the EPA guidance and LDEQ’s use of SILs
violate the CAA because the CAA “does not allow de minimis exceptions
to an applicant’s responsibility to demonstrate that it will not cause or
contribute to a NAAQS violation.” Sierra Club finds support for this
argument in the “broad, sweeping language” of the CAA, which restricts
any source that will “cause, or contribute to” a NAAQS violation. Sierra
Club cites to Bluewater Network v. E.P.A., 370 F.3d 1, 13 (D.C. Cir. 2004), for
the proposition that the word “contribute” as used in the CAA “has no
inherent connotation as to the magnitude or importance of the relevant
‘share’ in the effect; certainly it does not incorporate any ‘significance’
requirement.” Sierra Club further points out that, elsewhere in the CAA,
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Congress modified the word “contribution” with the word “significant” but
chose not to include that modifier in section 7475(a). See, e.g., 42 U.S.C.
§ 7407(d)(4)(v) (excluding from nonattainment areas portions where a state
demonstrates the sources “do not contribute significantly to a violation” of
NAAQS); § 7426 (limiting applicability of interstate pollution notification
requirements to new sources that “significantly contribute to levels of air
pollution in excess of” NAAQS). Based on this statutory language, Sierra
Club argues that neither the EPA nor LDEQ can alter the CAA’s
requirements by limiting air quality analyses to only those sources that
“significantly” contribute to NAAQS violations.
      In response, LDEQ asserts that neither the CAA nor Louisiana’s
SIP mandate any specific modeling analysis; rather, Congress gave the EPA
broad authority to determine how to demonstrate compliance with NAAQS.
AR75:4. And under this broad authority, the EPA has recommended that the
SIL screening process can suffice to make the necessary demonstration. See
Sierra Club v. U.S. Env’t Prot. Agency, 939 F.3d 649, 686 (5th Cir. 2019)
(“The EPA’s selection of modeling methods . . . is exactly the type of
decision for which ‘significant deference’ is appropriate.”). LDEQ
explained in its Public Comments Response Summary that “[t]he air quality
concentration levels that the EPA has identified as SILs do not function to
exempt a source from making the demonstration required.” AR71:33.
Instead, the SILs “provide a streamlined means” of showing compliance
with the CAA—in other words, the SIL analysis itself is the required
demonstration. AR71:33; AR91:14.
      Further, in response to Sierra Club’s textual arguments, LDEQ
points out that the D.C. Circuit, upon which Sierra Club relies heavily, has
often observed that the term “contribute” is ambiguous. See Catawba Cnty.
v. E.P.A., 571 F.3d 20, 35 (D.C. Cir. 2009) (listing “contribute” as one of
many words in a statute “suggest[ing] a congressional intent to leave
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unanswered questions to an agency’s discretion and expertise”); Env’t Def.
Fund, Inc. v. E.P.A., 82 F.3d 451, 459 (D.C. Cir.), amended sub nom. Env’t Def.
Fund v. E.P.A., 92 F.3d 1209 (D.C. Cir. 1996). Thus, LDEQ asserts that the
EPA’s determination that only “significant” contributions require extensive
air analyses should be afforded deference as a reasonable reading of the word
“contribute.” LDEQ also points to the label Congress chose for the PSD
program—“Prevention of Significant Deterioration”—as a helpful clue in
determining Congressional intent. See 42 U.S.C. § 7470 et seq. (emphasis
added). According to LDEQ, Congress gave the EPA “discretion to set the
conditions for determining whether a PSD applicant has complied with” the
CAA, and thus, the EPA was well within its authority in allowing state
agencies like LDEQ to use SILs. AR91:8.
       We agree with LDEQ and Commonwealth that the CAA does not
specify how a permit applicant or permitting authority must make the
required air quality demonstration. AR75:4. The plain language of the CAA
“authorizes the EPA to determine how the analysis is to be conducted,
including the use of air quality models.” AR75:4; see 42 U.S.C. § 7475(e)(1)
(“The review provided for in subsection (a) shall be preceded by an analysis
in accordance with regulations of the Administrator, promulgated under this
subsection . . .”). The plain language of the CAA does not, however, define
“contribute,” a word that courts have consistently found to be ambiguous.
See, e.g., Catawba Cnty., 571 F.3d at 35. The EPA’s interpretation of
“contribute” to allow for SILs and a shortened air quality analysis for
insignificant pollutants should therefore be given deference, where it
reasonably accounts for both the goals of the CAA and the public’s interest
in economic growth. See 42 U.S.C. § 7470 (explaining Congressional
declaration of purpose for the CAA); see also Groce v. Dep’t of Env’t Prot., 921
A.2d 567, 578 (Pa. Commw. Ct. 2007) (analyzing identical arguments
regarding SILs and finding that “Congress did not intend to prohibit any and
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all economic growth based on infinitesimally small values calculated using
highly developed and developing software”). LDEQ did not abuse its
discretion in relying on reasonable EPA guidance to use SILs to calculate
which pollutants will have an insignificant effect on the NAAQS.
       Further, it is worth noting that, for the four pollutants found to be in
excess of the SILs, LDEQ and Commonwealth went on to conduct a “full
impact analysis” to assess compliance with NAAQS. AR70:35; AR71:33;
AR90. This additional analysis modeled the facility’s projected pollutants
together with background sources located off-site, stretching as far as twenty
kilometers away. AR90:4-228-229; AR10:20-21. After this analysis, only one
pollutant exceeded the NAAQS: one-hour emissions of NO2. AR90:4-228-
229; AR10:41-44. Commonwealth and LDEQ then conducted a separate
“source contribution analysis” for NO2, which is discussed further below.
AR90:4-390; AR10:41. Looking at the air analyses as a whole, we cannot say
that LDEQ and Commonwealth cut corners or arbitrarily ignored
exceedances of NAAQS. Based on the extensive testing done, and the
deference owed to the EPA in determining how that testing is to be done, we
affirm LDEQ’s use of SILs in its permitting decision.
               ii.   Whether LDEQ reasonably applied the SIL for NO2.
       Sierra Club next argues that, even if SILs are valid under the CAA,
LDEQ did not apply them properly with respect to NO2. As mentioned,
LDEQ and Commonwealth conducted “refined modeling” for NO2
because the emission impacts were projected to be above the SILs. AR69:5.
As shown in the refined modeling table in LDEQ’s report, for the one-hour
averaging emissions period, the total NO2 concentration for the area was
projected to be over the NAAQS. AR69:6. Sierra Club seizes on the results
of this modeling to contend that “LDEQ could not issue Commonwealth’s
PSD permit without requiring mitigation to offset Commonwealth’s NO2
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impacts.” Sierra Club made these exact arguments during the public
comment period, and LDEQ responded by explaining in detail its reasoning
for approving the Commonwealth permits despite the initial modeling.
AR71:34–42.
       First, LDEQ noted that “modeled exceedances of a NAAQS do not
necessarily equate to actual exceedances of a NAAQS.” AR71:40. In fact,
the modeling replicates a worst-case scenario, assuming the worst-case
emissions from many industrial facilities in the area, combined with worst-
case meteorological conditions. AR71:40. According to LDEQ, the
modeling created a circumstance that was “improbable at best and, given the
number of sources modeled, likely never to occur.” AR71:40. However, even
in this worst-case scenario wherein all modeled sources emit their maximum
pollution, that alone is still unlikely to cause an exceedance of NAAQS. This
is because the exceedances are only expected when “background”
concentration is added in, and according to LDEQ, this is a “highly
conservative    exercise”    because    “the    actual     measured    ambient
concentrations used to represent background are in fact representative and
inclusive of contributions from the existing emission sources included in the
model.” AR71:40–41. In other words, LDEQ’s predictions “double count”
the effect of existing sources in the area. AR71:41.
       The EPA has issued guidance for what a state permitting agency
should do when “a cumulative impact analysis predicts a NAAQS
violation.” AR71:40. In this scenario, LDEQ may “compar[e] the proposed
source’s modeled contribution to that violation to the corresponding SIL
value.” AR71:40. “If the modeled impact is below the recommended SIL
value at the violating receptor during the violation, the EPA believes this will
be sufficient in most cases for a permitting authority to conclude that the
source does not cause or contribute to (is not culpable for) the predicted
violation.” AR71:40 (emphasis removed). LDEQ and Commonwealth
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followed this guidance and found that the facility’s contribution to the
exceedance of the one-hour NO2 NAAQS would be 0.07 µg/m3, far below
the SIL of 7.5 µg/m3. AR71:42. Thus, LDEQ concluded that the facility’s
potential contribution to any exceedance of NAAQS, as shown in the worst-
case scenario modelling, would be negligible. AR71:42. As a result, LDEQ
found additional mitigation measures unnecessary. AR71:42.
       Although Sierra Club asserts that LDEQ compounded the SILs error
by relying on the SIL for NO2 twice—once in the preliminary screening, and
once in the post-refined-modeling comparison—LDEQ followed relevant
EPA guidance precisely, all while explaining its entire process. This does not
appear to be a case where a State agency issued its decision “without
reason.” Reduction Credits, 885 So.2d at 10. Considering the detailed
modeling that LDEQ conducted and the vast amount of EPA guidance
supporting its analysis, we affirm LDEQ’s use of SILs to approve the
permits despite the initial modeled NO2 emissions.
               iii.   Whether LDEQ’s reliance on AP-42 factors was arbitrary.
       Finally, Sierra Club argues that, validity of SILs aside, LDEQ’s use
of AP-42 emissions factors “factually undermined” the SILs analysis,
making the permitting decision arbitrary and contrary to law. The AP-42
emissions factors are “representative value[s] that attempt[] to relate the
quantity of a pollutant released to the atmosphere with an activity associated
with the release of that pollutant.” EPA, Basic Information of Air Emissions
Factors and Quantification, https://www.EPA.gov/air-emissions-factors-
and-quantification/basic-information-air-emissions-factors-and-
quantification#About%20Emissions%20Factors (Nov. 30, 2023). The EPA
developed the AP-42 emissions factors for various combustion sources, so
that new sources that have yet to be built—such as the Commonwealth
facility—can look to the factors to determine projected operational
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emissions. AR71:118. Here, LDEQ and Commonwealth used AP-42 factors
as “default emission factors” to predict the likely pollutant outputs for the
facility. AR71:118.
       In contesting LDEQ’s analysis, Sierra Club emphasizes the EPA’s
warning in a 2020 guidance letter that “AP-42 emission factors should only
be used as a last resort” because they “are not likely to be accurate predictors
of emissions from any one specific source.” AR37:195 (emphasis removed);
AR71:114. However, LDEQ and Commonwealth point out that the EPA
only cautioned against AP-42 factors when used “in place of more
representative source-specific emissions value[s].” AR71:114. LDEQ argues
that AP-42 emissions factors are almost always required for projects like
Commonwealth’s because there are not yet direct emissions to monitor; the
facility has not been built, so it does not emit any measurable pollutants yet.
Commonwealth makes the same argument, emphasizing that “this is a
preconstruction permit and direct, site-specific emissions information is not
available.” Considering the specific factual scenario here, and where the
EPA has suggested that AP-42 emissions factors are suitable for this exact
situation, it was not an abuse of discretion for LDEQ and Commonwealth to
use AP-42 factors in their air quality analysis.
       Even if relying on the AP-42 factors themselves was not arbitrary,
Sierra Club argues that LDEQ should have relied on the “maximum”
factors, rather than the “average” factors, for its analysis. According to
Sierra Club, record evidence demonstrates that relying on the “maximum”
factors “would roughly triple Commonwealth’s potential to emit annual
NOx pollution.” However, LDEQ considered this argument in its Basis for
Decision and found that the extreme ends of the factor ranges are not likely
to be representative of actual emissions for the Commonwealth project.
AR71:107. For example, when responding to a comment that LDEQ should
use the maximum factor for fugitive VOC emissions, LDEQ explained that
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the use of the average factor was reasonable because it was not reasonable to
“expect every component at any facility to be leaking at an extraordinarily
high rate.” AR71:108. LDEQ did not act arbitrarily or contrary to law in
using the average AP-42 emission factors, set by the EPA, to determine
potential emissions from an LNG facility that has not yet been built.
          c. Whether LDEQ acted arbitrarily in authorizing the project’s
             BACT.
       Sierra Club next argues that LDEQ failed to require BACT for NOx
emitted from two sources of pollution in the facility: (1) Commonwealth’s
combustion turbines; and (2) Commonwealth’s oxidation system. While
acknowledging that “the applicant is not required to select the most effective
control option or the lowest emission limit that option is capable of,” Sierra
Club asserts that “the applicant must justify selecting anything other than
the most protective available option.” Here, Sierra Club believes LDEQ
failed to require that justification from Commonwealth and instead excused
incomplete emission analyses for BACT on the proposed LNG facility.
       First, some background on the BACT requirement. A key aspect of
the PSD permitting process requires the owner or operator of a new
stationary source to apply the BACT for the source’s expected air
pollutants—in simple terms, the facility must use the technology that best
limits emissions. The CAA specifically requires LDEQ to determine that
the proposed facility will be outfitted with the BACT for “each pollutant
subject to regulation.” 42 U.S.C. § 7475(a)(4). The EPA has established a
five-step, top-down approach for determining the BACT: (1) identify all
available control technologies; (2) eliminate the technically infeasible
options; (3) rank the remaining control technologies by effectiveness; (4)
evaluate the total impacts of the most effective control technologies and
document results; and (5) select the BACT. LAC 33:III:509; AR70:5–6.
“The most effective control option not eliminated in step 4 is selected as
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BACT.” AR70:6. While not a binding rule, LDEQ consistently uses this
EPA guidance for its PSD permitting program.
       “BACT        determinations      are     intrinsically    case-by-case
determinations.” Port Arthur Cmty. Action Network, 86 F.4th at 663. The
analysis “tak[es] into account energy, environmental, and economic impacts
and other costs.” 40 C.F.R. § 52.21(b)(12). It follows that this analysis
requires “expertise, experience, and procedural mechanisms” from
LDEQ’s end to conduct as thorough of a review as possible. Zen-Noh Grain
Corp. v. Consol. Env’t Mgmt., Inc., No. CIV.A. 12-1011, 2012 WL 6201871, at
*10 (E.D. La. Dec. 12, 2012), amended on denial of reconsideration, No. CIV.A.
12-1011, 2013 WL 3947186 (E.D. La. July 31, 2013).
       In the present case, Sierra Club takes issue with two of LDEQ’s
BACT determinations. The first deals with NOx emissions from
Commonwealth’s nine gas-fired combustion turbines. Sierra Club asserts
that the most effective technology to control emissions from these turbines
is a selective catalytic reduction (“SCR”) system paired with dry low NOx
burners. The main disagreement here centers around the approved
numerical emission limit of 2.5 ppmvd, compared to Sierra Club’s proposed
2.0 ppmvd limit based on its theory for increasing the system’s effectiveness.
However, as LDEQ explained in its response to Sierra Club’s public
comment on this issue, the effectiveness of the SCR system is “dependent
on many variables” and in reality, operates at a wide range of efficiency.
AR71:80. In other words, reducing the emissions by 0.5 ppmvd is not as
simple as Sierra Club makes it sound. LDEQ also addressed Sierra Club’s
assertion that many other facilities have achieved 2.0 ppmvd emission
numbers, noting that these other facilities are not comparable to the
Commonwealth project because they include “only combined cycle turbines
located at electrical generation facilities.” AR71:83. Commonwealth’s
facility will be built differently, in a different environment than other
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facilities. See AR71:83. Ultimately, LDEQ concluded that the BACT
determination of 2.5 ppmvd for the turbines was “appropriate and
reasonable” based on its thorough analysis. AR71:83.
       The    second    determination     concerns    NOx     emissions    from
Commonwealth’s oxidation system, which will use thermal oxidizers to
remove impurities from the natural gas before it is liquefied. Sierra Club
asserts that Commonwealth failed to consider a catalytic oxidizer, which
could result in lower overall NOx emissions. In its response to public
comments, however, LDEQ explained that, for a number of reasons, “the
use of catalytic oxidizers rather than thermal oxidizers . . . is not technically
feasible.” AR71:100. LDEQ highlighted the additional pollution that the
catalytic oxidizer would emit and explained that Commonwealth would need
to include additional machinery—that also could emit additional
pollutants—to combat the side effects of the oxidizer. AR71:100. In sum,
“[t]he addition of a scrubber to remove the trace constituents, a system to
manage the scrubber waste stream, and a natural gas-fired heater to raise the
temperature of the acid gas streams would needlessly add complexity to the
system, would increase capital and operating costs, and would be an
additional source of air emissions.” AR71:100. LDEQ argues that this
analysis suffices to establish the BACT and that, contrary to Sierra Club’s
assertions, cost estimates are not required as additional support for its
conclusion.
       As is evident from the administrative record, LDEQ carefully
responded to and rejected each of Sierra Club’s proposed BACTs during the
public comment period. While Sierra Club’s proposed control technologies
may be effective at reducing emissions, Sierra Club has failed to show
anything more than possible (and potentially infeasible) alternatives to
LDEQ’s already reasonable decisions. See St. James, 2024 WL 207859, at
*43–44 (holding that where the agency’s basis for decision reflected its
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consideration of emissions, their impact on the environment, and BACT on
those emissions, its determination was not arbitrary or capricious). Sierra
Club’s desire for Commonwealth to use different technology at its facility
does not mandate a conclusion that LDEQ acted arbitrarily in approving the
BACT that Commonwealth plans to use.
       Because LDEQ considered all relevant factors and articulated
reasons for its decisions regarding these specific technologies, this Court will
not disturb technical determinations made within LDEQ’s expertise. See
Alaska Dep’t of Env’t Conservation, 540 U.S. at 490 (explaining that, for the
purposes of BACT, the EPA disapproves a permit only in relatively rare
circumstances where “a state agency’s BACT determination is not based on
a reasoned analysis”) (quotation marks omitted); see also Maryland v. E.P.A.,
958 F.3d 1185, 1196 (D.C. Cir. 2020) (emphasizing that courts “give an
extreme degree of deference to [an agency’s] evaluation of scientific data
within its technical expertise”) (citation and internal quotation omitted)).
We decline to wade into these hyper-technical waters and supplant LDEQ’s
careful determinations, made with the benefit of time-consuming testing and
extensive analysis.
          d. Whether LDEQ violated Louisiana’s public trustee duty when
             considering the permit application.
       Article IX § 1 of the Louisiana Constitution establishes “[a] public
trust for the protection, conservation and replenishment of all natural
resources of the state.” Save Ourselves, 452 So.2d at 1154. In conjunction with
the constitutional standard, the Louisiana legislature codified a public trustee
duty to require an analysis of “[t]he potential and real adverse environmental
effects” of any proposed project that may affect air quality. La. R.S.
§ 30:2018(B)(1). Pursuant to the public trust doctrine, then, LDEQ must
“determine that adverse environmental impacts have been minimized or
avoided as much as possible consistently with the public welfare.” Save
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Ourselves, 452 So.2d at 1157. Sierra Club argues that, by granting the
preconstruction permits to Commonwealth here, LDEQ violated the public
trust doctrine. Essentially, Sierra Club makes similar arguments concerning
SILs and BACT detailed above, but asserts that LDEQ was required to go
above and beyond its CAA-based review of these issues to comply with its
public trustee duty.
        LDEQ provides three main responses: (1) this Court does not have
subject matter jurisdiction to review LDEQ’s compliance with state law that
is not included in the State’s SIP; (2) the Natural Gas Act preempts the
public trust doctrine 8; and (3) regardless, LDEQ did not violate its public
trustee duty. Commonwealth focuses primarily on argument (3), asserting
that LDEQ’s decision complied with its public trustee duty.
        As to LDEQ’s first argument, Sierra Club is correct that Louisiana’s
public trust doctrine has been incorporated into the SIP and is properly
before the Court now. In approving Louisiana’s SIP, the EPA specifically
incorporated LAC 33:III.101 and 111, which in turn authorize LDEQ to issue
permits in accordance with La. R.S. § 30:2001 et seq. See LAC 33:III.101(A)–
(B). Because of the explicit reference to the Louisiana statute that contains
the codified public trust doctrine, the doctrine acts as part of Louisiana’s
SIP. See LAC 33:III.501.A; LAC 33:III.537.A.II.
        Further, Louisiana courts have held that “all issues arising in the
context of LDEQ permit applications are public trustee issues; to find that
LDEQ acts as a public trustee only with respect to certain portions of its
determinations . . . would be absurd.” City of Baton Rouge v. La. Dep’t of Env’t
        _____________________
        8
         LDEQ’s arguments concerning preemption seem to rely on a scenario where its
permitting decision was consistent with the CAA and Louisiana’s SIP but inconsistent
with the public trust doctrine. Because we ultimately find that LDEQ’s permitting
decision was consistent with both, we do not address the alleged conflict between the two.
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Quality, 172 So.3d 13, 23 (La. App. 1 Cir. 4/28/15). In other words, LDEQ’s
compliance with its public trustee duty is inextricably intertwined with its
permitting analysis, and to separate the two would create confusion and
possible conflicting conclusions between state and federal courts reviewing
different aspects of the same permitting decisions. And, as a practical
consideration, any argument by LDEQ that it was not required to abide by a
public trustee duty is belied by LDEQ’s own permitting decision, which
contains detailed analyses of its compliance with that duty. See AR71. For
these reasons, Sierra Club’s arguments concerning the Louisiana public trust
doctrine are properly before us on appeal.
       As for the merits, LDEQ satisfied its public trustee duty here. In Save
Ourselves, Inc. v. La. Env’t Control Comm’n, the Louisiana Supreme Court
outlined the issues to be considered by the permit applicant and LDEQ
under the public trust doctrine. 452 So.2d at 1157. These issues are now
known as the “IT Questions,” and LDEQ analyzes them as three separate
inquiries: (1) whether “the potential and real adverse environmental effects
of the proposed facility [have] been avoided to the maximum extent
possible”; (2) whether “a cost benefit analysis of the environmental impact
costs balanced against the social and economic benefits of the proposed
facility demonstrate that the latter outweighs the former”; and (3) whether
“there [are] alternative projects which would offer more protection to the
environment than the proposed facility without unduly curtailing non-
environmental benefits.” Matter of Rubicon, Inc., 670 So.2d 475, 482 (La.
App. 1 Cir. 2/14/96) (explaining the “IT Decision” from Save Ourselves); see
also Blackett v. La. Dep’t of Env’t Quality, 506 So.2d 749, 753–54 (La. Ct. App.
1987), holding modified by Matter of Rubicon, Inc., 95-0108 (La. App. 1 Cir.
2/14/96), 670 So.2d 475 (listing the IT Questions as five separate questions);
AR71:1. These IT Questions have since been incorporated into the Louisiana
Revised Statutes. See La. R.S. § 30:2018(B).
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       LDEQ explicitly performed the IT Question analysis for the
Commonwealth permits and set forth twenty-nine pages of reasoning in
support. See, e.g., AR71:5-14 (analyzing the “concepts of alternative sites,
alternative projects, and mitigation measures” in detail); AR71:15-20
(analyzing “the potential and real adverse environmental impacts . . . to
ensure they are minimized to the maximum extent possible”); and AR71:20-
28 (performing a “cost/benefit analysis” that addresses the “social and
economic benefits of the proposed facility”). Much like its response to Sierra
Club’s original SIL and BACT arguments, LDEQ answered each concern
Sierra Club has raised with detailed, technical reasoning that demonstrates
exactly why LDEQ chose to issue the preconstruction permits to
Commonwealth. This certainly abides by the “rule of reasonableness”
inherent in the public trust doctrine. See Save Ourselves, 452 So.2d at 1157.
       While Sierra Club seems to argue that LDEQ must have gone beyond
satisfaction of the CAA’s requirements to also satisfy the public trust
doctrine, no court has ever suggested as much. And even if Sierra Club were
correct, LDEQ did go beyond the CAA’s requirements by carefully
considering each of the IT Questions included in the Louisiana statutes. See
AR71. Contrary to Sierra Club’s assertion, LDEQ did not rely solely on
minimum permitting requirements, but instead conducted a thorough air
emissions analysis and found that the benefits of the Commonwealth facility
were “major, significant, and tangible” so as to outweigh the de minimis
projected emissions. AR71:28. Unless “the actual balance of costs and
benefits that was struck was arbitrary or clearly gave insufficient weight to
environmental protection,” this Court should not substitute its own
judgment for that of LDEQ. Save Ourselves, 452 So.2d at 1159. Sierra Club
has not demonstrated that LDEQ’s balancing was unreasonable or arbitrary,
and therefore, we hold that LDEQ satisfied its public trustee duty when
issuing the Commonwealth permits.
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      IV.   Conclusion
      For the foregoing reasons, we DENY Sierra Club’s petition for
review and affirm LDEQ’s permitting decision.