Appellate Case: 23-9503 Document: 116-1 Date Filed: 04/28/2025 Page: 1 FILED United States Court of Appeals PUBLISH Tenth Circuit
UNITED STATES COURT OF APPEALS April 28, 2025
Christopher M. Wolpert FOR THE TENTH CIRCUIT Clerk of Court _______________________________________
CENTER FOR BIOLOGICAL DIVERSITY,
Petitioner,
v. No. 23-9503
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY; and MICHAEL S. REGAN, Administrator, United States Environmental Protection Agency
Respondents,
and
STATE OF COLORADO,
Intervenor - Respondent.
--------------------------------
AMERICAN PETROLEUM INSTITUTE,
Amicus Curiae.
___________________________________________
PETITION FOR REVIEW OF FINAL ACTION OF THE UNITED STATES ENVIRONMENTAL PROTECTION AGENCY _________________________________________ Appellate Case: 23-9503 Document: 116-1 Date Filed: 04/28/2025 Page: 2
Ryan Maher, Center for Biological Diversity, Washington, D.C., for Petitioner.
David Mitchell, United States Department of Justice, Environment and Natural Resources Division, Environmental Defense Section, Washington, D.C. (Todd Kim, Assistant Attorney General, United States Department of Justice, Environment and Natural Resources Division, Washington, D.C.; Everett Volk, Office of Regional Counsel, and Brian Doster, Office of General Counsel, United States Environmental Protection Agency, Washington, D.C., with him on the briefs), for Respondents.
Laura Terlisner Mehew, Senior Assistant Attorney General, Office of the Attorney General for the State of Colorado, Natural Resources and Environment, Denver, Colorado (Philip J. Weiser, Attorney General, and William Allen, Office of the Attorney General for the State of Colorado, Denver, Colorado, and Benjamin Elrod, Colorado Department of Law, Denver, Colorado), for Intervenor-Respondent.
John H, Bernetich, Jennifer L. Biever, and Dale T. Ratliff, Williams Weese Pepple & Ferguson PC, Denver, Colorado, filed an amicus curiae brief in support of Respondents and Intervenor-Respondent. _________________________________________
Before BACHARACH, BALDOCK, and CARSON, Circuit Judges. ___________________________________________
BACHARACH, Circuit Judge. ___________________________________________
Under federal law, states must adopt implementation plans to meet
national standards for ambient air quality. These plans are subject to
approval by the EPA.
Colorado adopted an implementation plan and revised it in 1997. In
2019, Colorado revised the plan again, changing the wording of a permit
requirement for new emission sources and adding to the definition of a key
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threshold to evaluate compliance. The EPA approved these revisions; and
the Center for Biological Diversity challenges this approval, arguing that
the revision to the permit requirement prevents regulators from blocking construction when a new source would generate excessive emissions and
the additional language in the definition allows regulators to disregard emissions during drilling, fracking, and well completion.
We reject the first challenge, concluding that the Center has not
shown an effect from the revised wording in the permit requirement. But
we agree with the Center on its second challenge, concluding that the EPA
acted arbitrarily and capriciously by failing to address the potential
emissions during drilling, fracking, and well completion.
Background
I. The states must adopt implementation plans providing for review of emissions from new sources.
The EPA and the states share responsibility for implementing the
Clean Air Act. US Magnesium, LLC v. EPA, 690 F.3d 1157, 1159 (10th Cir.
2012). For its part, the EPA caps the concentration of common pollutants in
the ambient air. 42 U.S.C. § 7409(a). (The Clean Air Act calls these caps
national ambient air quality standards. Id. § 7409(b)(1)–(2).) The states
must then adopt implementation plans to attain compliance with these
standards. Id. § 7410(a)(1). A state’s implementation plan
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is enforceable as state law and
becomes enforceable as federal law upon approval by the EPA.
See Espinosa v. Roswell Tower, Inc., 32 F.3d 491, 492 (10th Cir. 1994).
The implementation plans require states to establish a process for
granting permits that regulate construction and modification of stationary
sources of air pollution. Id. § 7410(a)(2)(C). The permitting process must
include
a procedure to determine whether a source will interfere with attainment of national air quality standards and
a mechanism to block construction or modification of stationary sources that would interfere with the attainment of these standards.
40 C.F.R. § 51.160(a)–(b).
II. Colorado adopts regulations on new stationary sources.
Given these requirements, Colorado has required permits for the
construction, operation, or modification of stationary sources that emit
pollutants. When a permit is requested, a state agency conducts a
preliminary analysis. The Center contends that during a preliminary
analysis, the state agency determines
whether the source would interfere with the attainment of national air quality standards and
whether the source would be eligible for a minor source permit or would need the more stringent permit required for major sources.
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Appellant’s Opening Br. at 16 (citing 5 Colo. Code Regs. § 1001-
5:3.B.III.B.7.c–d). According to the Center, these determinations are based
on the potential for emissions at the projected “commencement of
operation.” Id. (citing 5 Colo. Code Regs. § 1001-5:3.B.III.B.7).
III. Regulators consider Colorado’s proposed implementation plan.
Colorado undertook a rulemaking to revise parts of the
implementation plan. The Center participated in the rulemaking and
generally supported Colorado’s effort to update the implementation plan.
But the Center
didn’t explicitly take a position on any specific provisions and
said that it would promote improvements to the plan.
Colorado adopted the revisions, and the EPA initiated a rulemaking
to consider the revisions. The Center objected, urging the EPA to reject the
revisions to the permit requirement and the additional language defining
the threshold to evaluate compliance (commencement of operation). The
EPA rejected the objections and approved the revisions, leading the Center
to bring this challenge. The State of Colorado intervened to defend the
revisions.
Discussion
I. The Center did not waive its objections.
Colorado argues that the Center waived its objections by inviting the
alleged errors during Colorado’s rulemaking process. For this argument, 5 Appellate Case: 23-9503 Document: 116-1 Date Filed: 04/28/2025 Page: 6
Colorado relies on the invited error doctrine, which “prevents a party who
induces an erroneous ruling from being able to have it set aside on appeal.”
United States v. Burson, 952 F.2d 1196, 1203 (10th Cir. 1991). So this
doctrine might apply if the Center had asked the EPA to approve
Colorado’s revisions. But Colorado doesn’t suggest that the Center
supported the revisions during the EPA’s rulemaking; Colorado instead
points to comments in its own rulemaking process, which we’re not
reviewing.
Even if the invited error doctrine could be triggered by comments in
Colorado’s rulemaking (rather than the EPA’s), the doctrine wouldn’t apply
here. We apply the doctrine only when the record clearly shows that a party
previously supported an action and later challenges it on appeal. See
United States v. Flechs, 98 F.4th 1235, 1252 n.15 (10th Cir. 2024)
(“Invited error must be clear from the record.”).
The Center didn’t clearly support the revisions that it is now
challenging. In the Colorado proceedings, the Center stated only that it
“generally support[ed]” the updating of Colorado’s implementation plan,
cautioning that it wasn’t taking any “position on the specific provisions.”
R. 902. In making these statements, the Center didn’t clearly support either
of the disputed revisions.
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II. We evaluate the EPA’s approval under the arbitrary-and- capricious standard.
Because the invited error doctrine doesn’t apply, we must review the
EPA’s decision, guided by the Administrative Procedure Act. Ariz. Pub.
Serv. Co. v. EPA, 562 F.3d 1116, 1122 (10th Cir. 2009). Under this Act, the
decision is unlawful if the EPA acted arbitrarily and capriciously by failing
to consider an important aspect of the problem or to provide a rational
explanation for the decision. Id. at 1122–23; see 5 U.S.C. § 706(2)(A).
III. The EPA didn’t err in approving the revision to the permit requirement.
The Center challenges a revision in Colorado’s wording of its
requirement for a permit. Before the revision, the implementation plan had
said that regulated parties couldn’t “[c]ommence construction or modify” a
stationary source without a permit. R. 47. In 2019, Colorado revised the
implementation plan to say that regulated entities couldn’t “[c]onstruct,
operate, or modify” a stationary source without a permit. Id. 12, 47.
The Center challenges the revision based on two arguments:
1. Colorado’s program violates federal regulations by failing to block some projects that would interfere with the attainment of national air quality standards.
2. The EPA failed to assess the effect of the revision on Colorado’s progress toward attainment of these standards.
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We reject both arguments. The first argument involves a perceived
flaw in permits unrelated to the language in the 2019 revisions. 1 The
second argument disregards the EPA’s findings.
A. The revisions didn’t cause the alleged violation.
The first argument consists of three steps:
1. Under federal regulations, an implementation plan must block construction of stationary sources that would interfere with the attainment of national air quality standards. 40 C.F.R. § 51.160(a)–(b).
2. Colorado prohibits the construction, operation, or modification of stationary sources without a permit.
3. Colorado issues general permits that allow construction upon submission of an application (before the state has considered the effect on air quality).
The problem with this argument is that the disputed revision didn’t affect
Colorado’s general permits.
Before the revision, operators of stationary sources needed a permit
before constructing the source. The revision didn’t address that
requirement. But the Center complains that some permits allow the start of
construction as soon as someone submits an application (before regulators
can assess the effect on air quality).
1 Under certain circumstances, revisions might reopen a regulatory scheme to new challenges. See Pub. Citizen v. Nuclear Regulatory Comm’n, 901 F.2d 147, 150–51 (D.C. Cir. 1990) (discussing whether an agency had reopened an issue). But the Center does not argue that these circumstances existed here.
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If the Center is right, its complaint lies with Colorado’s process for
issuing general permits. But if Colorado’s process is defective, that fault
doesn’t lie with the 2019 revisions. In fact, the EPA has never approved a
provision in Colorado’s implementation plan that would allow construction
to start before the owner gets a permit. So even if the general permits
served to bypass federal regulations, the violation would not arise from the
2019 revisions to the implementation plan.
The Center nonetheless argues that the EPA wrongly assumed that
sources couldn’t start construction before the issuance of a permit. From
the EPA’s standpoint, however, this alleged assumption would have been
right because Colorado’s implementation plan had already required a
permit prior to construction. 5 Colo. Code Regs. § 1001-5:3B.III.I.2. If
Colorado regulators are issuing permits in violation of the implementation
plan, that violation wouldn’t stem from the 2019 revision. So we reject this
challenge.
B. The EPA did make the required finding.
The Center also points to federal law, which requires the EPA to
reject a revision if it would interfere with the state’s attainment of national
air quality standards. 42 U.S.C. § 7410(l). According to the Center, the
EPA violated this requirement by approving the revision without evaluating
Colorado’s progress toward attainment of national air quality standards. We
disagree. The EPA expressly found that the revision would not interfere
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with the attainment of national air quality standards, and the Center has not
shown an error in that finding.
The Center argues that the EPA assumed that Colorado’s revision
wouldn’t create substantive changes in the permit requirement. But that
assumption is right: Colorado just changed
commence construction or modify to
construct, operate, or modify.
And a separate provision already required a permit to “commence” any of
these activities. 5 Colo. Code Regs. § 1001-5.3B.III.I.2.a, c. So the
changes simply
deleted the verb commence before the noun construction to avoid a redundancy,
turned a nominalization (construction) into a verb (construct), and
added a second verb (operate).
These changes didn’t affect the meaning. So if the EPA had assumed that
the changes to the implementation plan weren’t substantive, that
assumption would have been right.
* * *
In sum, the Center has not shown that the EPA acted arbitrarily or
capriciously by approving Colorado’s revised wording of the permit
requirement. So we reject the Center ’s challenge to this revision.
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IV. The EPA erred in approving the revised definition of the term commencement of operation.
The 2019 revision also added language to the definition of the term
commencement of operation. Before the revision, the definition had stated:
“A new source commences operation when it first conducts the activity that
it was designed and permitted for (i.e., producing cement or generating
electricity).” R. 1815. The revision added a second sentence:
In addition, for oil and gas well production facilities, commencement of operations is the date any permanent production equipment is in use and product is consistently flowing to sales lines, gathering lines or storage tanks from the first producing well at the stationary source, but no later than the end of well completion operations (including flowback).
Id.
A. The Center did not forfeit an objection to the revised definition.
The EPA and Colorado argue that the Center forfeited its objection by
failing to raise it during the EPA’s rulemaking. To address this argument,
we consider whether the Center made the objection with “reasonable
specificity.” 42 U.S.C. § 7607(d)(7)(B). Under this standard, the Center
could refine its argument in the appeal as long as the objection had alerted
the EPA to the general substance. WildEarth Guardians v. EPA, 770 F.3d
919, 943 (10th Cir. 2014).
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1. The Center’s comments alerted the EPA to the general substance of the argument.
In the EPA rulemaking, the Center complained that the revised
definition “excludes emissions prior to operations such as [emissions from]
drilling, fracking, and completion.” R. 3993. The Center makes the same
argument here.
Granted, the Center has elaborated here on how the revision
disregards emissions from drilling, fracking, and well completion. Even
without that elaboration, however, the EPA understood that the Center was
objecting to the definition of commencement of operation, responding that
the revision had only been “procedural” and hadn’t excluded “any types of
sources from review.” Id. 6.
The EPA argues that it understood the comment to address the part of
the definition that had existed since 1997. 2 But that understanding rests on
a cramped reading of the Center ’s comment. The Center focused its
comment solely on the new definition’s alleged exclusion of “pollution
emitting activities such as drilling wells, ‘fracking’ wells, and completing
wells.” Id. 3993. This focus should have alerted the EPA to the Center ’s
concern with the new language covering emissions from drilling, fracking,
2 That definition didn’t refer to oil-and-gas operators; the revision purported to explain how the definition applied to oil-and-gas facilities. 87 Fed. Reg. 16, 439–40 (Mar. 23, 2022). 12 Appellate Case: 23-9503 Document: 116-1 Date Filed: 04/28/2025 Page: 13
and well completion. So the Center adequately preserved the issue even if
the EPA had misunderstood the comment.
2. The comment sufficed even though the Center didn’t use the term preliminary analysis or cite some relevant regulations.
The EPA argues that the Center ’s comments didn’t refer to
the term preliminary analysis,
the other relevant parts of Colorado’s implementation plan, or
the federal regulation defining a major source and the potential to emit.
But a commenter can explain its concern without using technical language
or citing the relevant regulations. The D.C. Court of Appeals addressed a
similar issue in National Petrochemical & Refiners Association v. EPA, 287
F.3d 1130 (D.C. Cir. 2002) (per curiam). There a comment stated that the
product had worked “only . . . within a narrow temperature range,” but
didn’t refer to the regulatory term (cold-start portion). Id. at 1139. The
D.C. Circuit concluded that the commenter had reasonably presented the
issue without using the technical term. Id.
The same is true here. The Center ’s comments didn’t refer to the term
preliminary analysis. But the Center otherwise stated its concern with the
new carveout for pollutants emitted during drilling, fracking, and well
completion. The EPA should have understood the Center ’s concern without
the legal term preliminary analysis. See NPCA v. BLM, 606 F.3d 1058,
1065 (9th Cir. 2010) (stating that a commenter doesn’t need to recite its 13 Appellate Case: 23-9503 Document: 116-1 Date Filed: 04/28/2025 Page: 14
argument “in precise legal terms”). Likewise, the Center could alert the
EPA to the general substance of the concerns without citing every relevant
regulation. See WildEarth Guardians v. EPA, 770 F.3d 919, 942–43 (10th
Cir. 2014) (holding that a commenter ’s failure to cite a particular
regulation was “not fatal” to preservation of a regulatory challenge).
In sum, we conclude that the Center did not forfeit its objection to
the revised definition.
B. The EPA improperly assumed that the revision wasn’t substantive.
The Center contends that the revised definition creates a new
exclusion for pollutants emitted before a well starts producing. The EPA
apparently credited Colorado’s characterization of the revision as
“clarifying.” R. 6. But the EPA didn’t independently assess that
characterization. By failing to independently assess that characterization,
the EPA acted arbitrarily and capriciously. See Ariz. Pub. Serv. Co. v. EPA,
562 F.3d 1116, 1123 (10th Cir. 2009) (stating that an action is arbitrary and
capricious when the agency “entirely failed to consider an important aspect
of the problem”).
Colorado argues that the revisions didn’t create the alleged
environmental problems because
the revised definition hadn’t changed the method of calculating potential emissions and 14 Appellate Case: 23-9503 Document: 116-1 Date Filed: 04/28/2025 Page: 15
the Center is relying on emissions from nonroad engines even though they are exempt from regulations.
But the EPA didn’t independently assess the first explanation or rely on the
second one. To the contrary, the EPA approved the revised definition based
solely on Colorado’s statement that it wasn’t changing the meaning of the
term commencement of operation. R. 6; see p. 14, above. So we cannot
uphold the EPA’s approval based on Colorado’s arguments defending the
revision. See Alameda Water & Sanitation Dist. v. Browner, 9 F.3d 88, 91
(10th Cir. 1993) (“A court may not uphold an agency action on grounds not
relied on by the agency.”).
C. The appropriate remedy is remand rather than vacatur.
Because the EPA’s acceptance of Colorado’s characterization was
arbitrary and capricious, we must decide whether to vacate the approval or
to remand for reconsideration. For that decision, we consider two factors:
1. the seriousness of the error and the likelihood that the EPA can justify its decision on remand and
2. the disruptive consequences of vacatur.
See Diné Citizens Against Ruining Our Env’t v. Haaland, 59 F.4th 1016,
1049 (10th Cir. 2023) (citing Allied-Signal v. U.S. Nuclear Regulatory
Comm’n, 988 F.2d 146, 150–51 (D.C. Cir. 1993)). The first factor supports
remand, and the second factor does not tilt heavily either way.
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1. The EPA may be able to justify its decision on remand.
For the first factor, we consider whether the EPA may be able to
justify the revised language with a fuller discussion. Diné Citizens, 59
F.4th at 1049. Of course, we can’t know whether the error is curable until
the EPA explains why it approved the change. So we can consider only the
possibility that the EPA might be able to justify the revision with a fuller
explanation. Shafer & Freeman Lakes Envir. Conserv. Corp. v. FERC, 992
F.3d 1071, 1096 (D.C. Cir. 2021). This inquiry requires some measure of
speculation about the EPA’s ability to justify the revision.
Colorado has argued that the revision serves only to clarify what the
prior plan allowed. On remand, the EPA can independently evaluate that
argument. To do so, the EPA can assess the applicability of the prior
definition to oil-and-gas wells and determine whether the revision creates a
substantive change. If the revised definition doesn’t affect the timing of an
oil-and-gas well’s commencement of operations, a fuller explanation might
salvage the revised definition. See Dep’t of Homeland Sec. v. Regents of
the Univ. of Calif., 591 U.S. 1, 20–21 (2020) (stating that the agency may
justify a decision by providing a fuller articulation of an observation that
had earlier been conclusory).
The Center insists that the EPA can’t salvage its approval by
supplementing the record. But the EPA hasn’t said how the prior definition
applied to oil-and-gas wells. Depending on how the prior definition had
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applied to oil-and-gas wells, the EPA might have been right to characterize
the revision as a clarification rather than a substantive change.
2. The potential for disruption doesn’t clearly weigh for or against vacatur.
The second factor concerns the potential disruption from vacatur.
Diné Citizens Against Ruining Our Env’t v. Haaland, 59 F.4th 1016, 1049
(10th Cir. 2023). When evaluating this factor, we consider disruptive
consequences for the regulated industry and the interests protected by the
disputed policy. Id. These consequences don’t clearly weigh for or against
vacatur.
The impact of vacatur turns partly on the impact of the 2019
revision. The Center insists that the revision created a new carveout for
emissions from drilling, fracking, and well completion; the EPA counters
that the revision served only to clarify the existing definition. If the Center
is right, vacatur would create an apparent difference between federal law
and state law: The carveout for drilling, fracking, and well completion
would disappear under federal law and remain under state law. See
Espinosa v. Roswell Tower, Inc., 32 F.3d 491, 492 (10th Cir. 1994) (noting
that provisions of an implementation plan, when approved by the EPA,
have “the force and effect of federal law”). But the difference could prove
illusory because Colorado can’t implement a permitting scheme that
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undermines a federally approved implementation plan. 42 U.S.C. §§ 7416,
7604(f).
On the other hand, the Center argues that
vacatur would help bring Colorado’s regulations into compliance with federal law and
continuation of the revised definition would allow greater emissions from oil-and-gas wells.
But these arguments assume that the revised definition created a
substantive change, and we cannot assess that assumption until the EPA
provides a fuller explanation.
The parties’ respective arguments thus turn on whether the revision
created a substantive change. And we can’t evaluate that possibility in a
meaningful manner until the EPA provides a fuller explanation. In these
circumstances, the second factor doesn’t tilt heavily for or against vacatur.
The second factor doesn’t weigh heavily in either direction, but the
first factor supports remand without vacatur. So we remand to the EPA
without vacating its prior approval of the revised definition of the term
commencement of operation.
D. We decline to impose a deadline for the EPA to act on remand.
In its reply brief, the Center asks us to impose a deadline for the EPA
to provide a fuller explanation. Because the Center didn’t make this
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request in its opening brief, the EPA hasn’t had a chance to respond.
Without input from the EPA, we have little basis to assess the feasibility of
particular deadlines. We thus decline to apply an arbitrary deadline for the
EPA to provide a fuller explanation for the revised definition. 3
Disposition
For the revised permit requirement, we deny the petition for review.
But we grant the petition as to the revised definition of the term
commencement of operation. With this grant of the petition, we remand to
the EPA for further explanation of the decision to approve the revised
definition.
3 If the EPA takes too long, the Center can seek an order compelling expedited action. See 5 U.S.C. § 706(1) (authorizing reviewing courts to “compel agency action . . . unreasonably delayed”).