Center for Biological Diversity v. EPA

U.S. Court of Appeals for the Tenth Circuit
Center for Biological Diversity v. EPA, 134 F.4th 1271 (10th Cir. 2025)

Center for Biological Diversity v. EPA

Opinion

 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
                _________________________________________
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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,
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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).
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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
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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
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           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”).

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Reference

Status
Published