Petition for Writ of Certiorari — Chamber of Commerce, et al., Petitioners v. Environmental Protection Agency, et al.

Supreme Court briefAug 28, 2026

Ask Donna

What actually matters in this document.

Text

No. ____

IN THE

Supreme Court of the United States

________________________________

CHAMBER OF COMMERCE OF THE UNITED STATES

OF AMERICA, ET AL.

Petitioners,

UNITED STATES ENVIRONMENTAL PROTECTION

AGENCY; LEE ZELDIN, ADMINISTRATOR, ET AL.

Respondents.

________________________________

ON PETITION FOR WRIT OF CERTIORARI TO THE UNITED

STATES COURT OF APPEALS FOR THE DISTRICT OF

COLUMBIA CIRCUIT

________________________________

PETITION FOR A WRIT OF CERTIORARI

________________________________

LUCINDA MINTON

LANGWORTHY

ERICA N. PETERSON

HUNTON ANDREWS KURTH

LLP

2200 Pennsylvania Avenue,

NW, Suite 900

Washington, D.C. 20037

(202) 955-1500

ELBERT LIN

Counsel of Record

DAVID M. PARKER

HUNTON ANDREWS KURTH

LLP

951 E. Byrd St., East Tower

Richmond, VA 23219

elin@Hunton.com

(804) 788-8200

Counsel for Petitioners Chamber of Commerce of the

United States of America, American Cement Association,

American Chemistry Council, American Forest & Paper

Association, American Petroleum Institute, American

Wood Council, National Association of Manufacturers,

and National Mining Association

(Additional counsel on signature page)

QUESTIONS PRESENTED

The decision below raises two important questions

about the U.S. Environmental Protection Agency’s

(EPA’s) authority to revise a National Ambient Air

Quality Standard (NAAQS). Such revisions reset the

baseline for a legion of regulations that affect virtually

every significant source of the regulated pollutant,

and virtually all economic sectors, in the nation.

Section 109(d)(1) of the Clean Air Act requires

EPA, every five years, to complete a “thorough review”

of the latest science before revising a NAAQS, and

also allows EPA to act “earlier or more frequently.”

This provision requires a thorough review before any

revision. But here, EPA claimed for the first time that

it can skip that review when it revises a NAAQS

between five-year intervals. EPA then confessed

error. But the D.C. Circuit upheld the revision—based

on a different statutory provision that EPA had not

invoked (and even disavowed), and that in any event

does not excuse the thorough review.

The questions presented are:

Whether EPA may revise a NAAQS without the

“thorough review” required by section 109(d)(1)

simply because it acts “earlier or more

frequently” than mandated.

Whether EPA must consider costs and

attainability when exercising discretion to

review and revise a NAAQS “earlier or more

frequently” than mandated.

PARTIES TO THE PROCEEDING

Petitioners in this Court, who were also

Petitioners below, are the Chamber of Commerce of

the United States of America; American Cement

Association; American Chemistry Council; American

Forest & Paper Association; American Petroleum

Institute; American Wood Council; National

Association of Manufacturers; National Mining

Association; President of the Arizona State Senate

Warren Petersen; Speaker of the Arizona House of

Arizona

Representatives

Steve

Montenegro1;

Chamber of Commerce and Industry; and the

Essential Minerals Association.

Additional

petitioners

below

were

the

Commonwealth of Kentucky, State of West Virginia,

State of Alabama, State of Alaska, State of Arkansas,

State of Florida, State of Georgia, State of Idaho, State

of Indiana, State of Iowa, State of Kansas, State of

Louisiana, State of Mississippi, State of Missouri,

State of Montana, State of Nebraska, State of North

Dakota, State of Ohio, State of Oklahoma, State of

South Carolina, State of South Dakota, State of

Tennessee, State of Utah, State of Wyoming, State of

Texas, and the Texas Commission on Environmental

Quality.

Respondents below were the United States

Environmental Protection Agency and Lee Zeldin,

Speaker Steve Montenegro was substituted for former

Speaker Ben Toma by operation of Federal Rule of Appellate

Procedure 43(c)(2).

iii

Administrator,

United

Protection Agency.

States

Environmental

Respondent-Intervenors below were the Sierra

Club;

Citizens

for

Pennsylvania’s

Future

(PennFuture); Conservation Law Foundation;

Northeast Ohio Community Resilience Centre

(formerly known as Northeast Ohio Black Health

Coalition); the Rio Grande International Study

Center; the Natural Resources Defense Council; the

State of California; State of Arizona; State of

Connecticut; District of Columbia; State of Illinois;

State of Maryland; Commonwealth of Massachusetts;

State of Michigan; State of Minnesota; State of New

Jersey; State of New York; State of Oregon;

Commonwealth of Pennsylvania; State of Rhode

Island; State of Vermont; State of Washington; State

of Wisconsin; City of New York; the Alliance of Nurses

for Healthy Environments; American Lung

Association; Environmental Defense Fund; and

Harris County, Texas.

RULE 29.6 DISCLOSURE STATEMENT

Petitioners have no parent corporations, and no

publicly held company has 10% or greater ownership

in any of petitioners.

TABLE OF CONTENTS

Page

QUESTIONS PRESENTED ....................................... i

PARTIES TO THE PROCEEDING ........................... ii

RULE 29.6 DISCLOSURE STATEMENT ............... iv

TABLE OF AUTHORITIES .................................... viii

OPINION BELOW ..................................................... 1

JURISDICTION ......................................................... 1

STATUTORY PROVISIONS INVOLVED ................ 1

INTRODUCTION ....................................................... 4

STATEMENT ............................................................. 8

I. Statutory and regulatory background.................. 8

A. The cascading consequences of a National

Ambient Air Quality Standard (NAAQS) ....... 8

Setting an initial NAAQS ...................... 8

Revising a NAAQS ............................... 10

B. Requirements for promulgating and

revising a NAAQS.......................................... 12

II. The proceedings below ........................................ 14

A. The revised PM2.5 standard ........................... 14

B. The D.C. Circuit litigation ............................ 17

REASONS FOR GRANTING THE PETITION ...... 20

I. The D.C. Circuit erred by excusing EPA

from the Clean Air Act’s “thorough review”

requirement. ........................................................ 21

A. Section 109(d)(1) requires a thorough

review for all NAAQS revisions, whether

on- or off-cycle. ............................................... 21

B. The D.C. Circuit’s contrary theory of

statutory authority was improper and

incorrect. ........................................................ 25

The D.C. Circuit violated the principle

of party presentation. ..................................... 25

The D.C. Circuit violated Chenery. ..... 27

The D.C. Circuit’s theory was wrong

on the merits. .................................................. 31

a) Section 109(b) does not confer revision

authority. .............................................. 31

b) Any prior revision authority is

constrained by section 109(d)(1). ......... 32

II. The D.C. Circuit wrongly held that EPA

cannot consider costs and attainability in

deciding whether to review and revise a

NAAQS off-cycle. ................................................. 38

III.The questions presented are exceptionally

important............................................................. 42

CONCLUSION ......................................................... 44

vii

APPENDIX MATERIALS

VOLUME I:

APPENDIX A: Opinion of the U.S. Court of

Appeals for the District of Columbia Circuit

Denying Petitions for Review and EPA’s Motion

for Vacatur, Commonwealth of Kentucky v.

EPA, No. 24-1050 (consolidated with Nos. 241051, 24-1052, 24-1073, 24-1091) (D.C. Cir.

June 26, 2026) .......................................................... 1a

APPENDIX B: U.S. Environmental Protection

Agency, Reconsideration of the National

Ambient Air Quality Standards for Particulate

Matter; Final Rule, 89 Fed. Reg. 16,202 (Mar.

6, 2024) (excerpts) .................................................. 46a

VOLUME II:

APPENDIX C: Clean Air Act § 109, 42 U.S.C.

§ 7409 .................................................................... 466a

APPENDIX D: EPA, Responses to Significant

Comments on the 2023 Proposed Rule for the

Reconsideration of the National Ambient Air

Quality Standards for Particulate Matter

(undated), Docket No. EPA-HQ-OAR-20150072-6025 (excerpts) ............................................ 470a

APPENDIX E: Declaration of Aaron Szabo

(Nov. 24, 2025) ...................................................... 500a

viii

TABLE OF AUTHORITIES

Page(s)

Cases

Abramski v. United States,

573 U.S. 169 (2014) .............................................. 34

All. for Cannabis Therapeutics v. Drug

Enf’t Admin.,

930 F.2d 936 (D.C. Cir. 1991) .............................. 38

All. of Nurses for Healthy Env’ts v.

Zeldin,

No. 26-cv-03118, 2026 WL 2078145

(N.D. Cal. July 17, 2026) ................................ 7, 20

Am. Farm Bureau Fed’n v. EPA,

559 F.3d 512 (D.C. Cir. 2009) (per

curiam) ................................................................. 34

Am. Trucking Ass’ns, Inc. v. EPA,

283 F.3d 355 (D.C. Cir. 2002) .............................. 34

Apogee Coal Co. v. Off. of Workers’

Comp. Programs,

113 F.4th 751 (7th Cir. 2024) .............................. 29

Bank of Am., N.A. v. F.D.I.C.,

244 F.3d 1309 (11th Cir. 2001) ............................ 29

Bartenwerfer v. Buckley,

598 U.S. 69 (2023) ................................................ 35

Clark v. Sweeney,

607 U.S. 7 (2025) (per curiam) ...................... 25, 27

Dep’t of Homeland Sec. v. Regents of the

Univ. of California,

591 U.S. 1 (2020) ...................................... 28, 30, 44

Encino Motorcars, LLC v. Navarro,

579 U.S. 211 (2016) .............................................. 44

Env’t Comm. of Fla. Elec. Power

Coordinating Grp., Inc. v. EPA,

94 F.4th 77 (D.C. Cir. 2024) (per

curiam) ................................................................. 42

EPA v. Calumet Shreveport Refining,

L.L.C.,

145 S. Ct. 1735 (2025) .......................................... 34

Exxon Corp. v. Hunt,

475 U.S. 355 (1986) .............................................. 23

FDA v. Wages & White Lion Invs., LLC,

604 U.S. 542 (2025) .............................................. 28

Kentucky v. EPA,

179 F.4th 963 (D.C. Cir. 2026) .............................. 1

Learning Res., Inc. v. Trump,

607 U.S. 229 (2026) .............................................. 37

Loper Bright Enters. v. Raimondo,

603 U.S. 369 (2024) .................................. 21, 29, 37

Margolin v. Nat’l Ass’n of Immigr.

Judges,

146 S. Ct. 1285 (2026) (per curiam) .............. 26, 27

Michigan v. EPA,

576 U.S. 743 (2015) ........................................ 38, 41

Mississippi v. EPA,

744 F.3d 1334 (D.C. Cir. 2013) (per

curiam) ................................................................. 34

Montgomery v. Caribe Transp. II, LLC,

146 S. Ct. 1199 (2026) .......................................... 36

Motor Vehicle Mfrs. Ass’n v. State Farm

Mut. Auto. Ins. Co.,

463 U.S. 29 (1983) ................................................ 44

Murray Energy Corp. v. EPA,

936 F.3d 597 (D.C. Cir. 2019) (per

curiam) ................................................................. 11

Nat. Res. Def. Council v. Regan,

67 F.4th 397 (D.C. Cir. 2023) .............................. 32

Ohio v. EPA,

603 U.S. 279 (2024) ................................................ 9

Oklahoma v. Castro-Huerta,

597 U.S. 629 (2022) .............................................. 36

RadLAX Gateway Hotel, LLC v.

Amalgamated Bank,

566 U.S. 639 (2012) .............................................. 32

Richards v. United States,

369 U.S. 1 (1962) .................................................. 23

Ross v. Blake,

578 U.S. 632 (2016) .............................................. 21

SEC v. Chenery Corp.,

318 U.S. 80 (1943) .................................... 18, 28, 30

Skidmore v. Swift & Co.,

323 U.S. 134 (1944) ........................................ 36, 37

United States v. Sineneng-Smith,

590 U.S. 371 (2020) .................................. 25, 27, 30

United States v. Williams,

553 U.S. 285 (2008) .............................................. 23

Varity Corp. v. Howe,

516 U.S. 489 (1996) .............................................. 32

Whitman v. American Trucking Ass’ns,

531 U.S. 457 (2001) ..................................................

...................... 6, 7, 17, 18, 19, 20, 25, 29, 39, 40, 41

Statutes

17 U.S.C. § 102(a) ...................................................... 24

18 U.S.C. § 1084(a) .................................................... 24

28 U.S.C. § 1254(1) ...................................................... 1

42 U.S.C. § 7407(d)(1)(A) .................................. 8, 9, 11

xii

42 U.S.C. § 7407(d)(1)(B)(i) ................................... 9, 11

42 U.S.C. § 7408 .................................... 1, 3, 14, 22, 23

42 U.S.C. § 7408(a)(1)(A)–(B)...................................... 8

42 U.S.C. § 7408(a)(2) ............................. 13, 25, 35, 36

42 U.S.C. § 7409 ................................................ 2, 3, 12

42 U.S.C. § 7409(a) .............................................. 12, 31

42 U.S.C. § 7409(b)(1) ............................. 12, 25, 31, 36

42 U.S.C. § 7409(d)(1) ................. 12, 13, 19, 21, 24, 33

42 U.S.C. § 7409(d)(2)(A)–(B) ............................. 13, 35

42 U.S.C. § 7475(a)(3) ............................................... 10

42 U.S.C. § 7501(3) .................................................... 11

42 U.S.C. § 7502(c)(6) ................................................ 10

42 U.S.C. § 7502(e) .............................................. 11, 44

42 U.S.C. § 7503(a)(2) ......................................... 11, 42

42 U.S.C. § 7510a(a)(2) ............................................. 10

42 U.S.C. § 7602(z) ...................................................... 9

42 U.S.C. § 7603 ........................................................ 36

42 U.S.C. § 7607(b)(1) ......................................... 17, 20

xiii

Legislative History

Clean Air Act Amendments of 1977,

Pub. L. No. 95-95, § 106(a), 91 Stat.

685, 691 (1977) ..................................................... 35

Federal Register

85 Fed. Reg. 82,684 (Dec. 18, 2020) .......................... 14

88 Fed. Reg. 5558 (Jan. 27, 2023) ....................... 10, 15

89 Fed. Reg. 16,202 (Mar. 6, 2024) ........... 1, 13, 14, 15

Miscellaneous

EPA, EPA-452/R-22-004, Policy

Assessment for the Reconsideration

of the National Ambient Air Quality

Standards for Particulate Matter

(May 2022), EPA-HQ-OAR-20150072-1584 ............................................................. 13

EPA, Response to Comments (undated),

EPA-HQ-OAR-2015-0072-6025 ... 16, 17, 19, 30, 38

Heinzerling, Lisa, The Clean Air Act

and the Constitution, 20 ST. LOUIS U.

PUB. L. REV. 121 (2001) .......................................... 8

xiv

Press Release, EPA Initiates New

Review of the Ozone National

Ambient Air Quality Standards to

Reflect the Latest Science (Aug. 21,

2023), https://tinyurl.com/mrhc329m

(last visited Aug. 26, 2026) .................................. 39

Press Release, EPA, EPA to Reexamine

Health Standards for Harmful Soot

that Previous Administration Left

Unchanged (June 10, 2021),

https://tinyurl.com/2uvxmymj (last

visited Aug. 26, 2026) .......................................... 15

SCALIA, ANTONIN & BRYAN A. GARNER,

READING LAW: THE INTERPRETATION

OF LEGAL TEXTS (2012) ......................................... 24

Statement by the President on the

Ozone National Ambient Air Quality

Standards (Sept. 2, 2011),

https://tinyurl.com/ccdte5n7 ................................ 39

Sunstein, Cass R., Office of Information

and Regulatory Affairs

Administrator, Letter to Lisa P.

Jackson, EPA Administrator (Sept.

2, 2011) https://tinyurl.com/3ykfcy7n

(last visited Aug. 26, 2026) .................................. 39

U.S. Chamber of Commerce, Comments

on Proposed Rule, U.S.

Environmental Protection Agency:

Reconsideration of the National

Ambient Air Quality Standards for

Particulate Matter, 88 Fed. Reg.

5558–5719 (Jan. 27, 2023) (Mar. 28,

2023), EPA-HQ-OAR-2015-00722428 ...................................................................... 10

WEBSTER’S NEW WORLD DICTIONARY,

SECOND COLLEGE EDITION (1972) ........................ 31

OPINION BELOW

The opinion of the U.S. Court of Appeals for the

District of Columbia Circuit is reported at 179 F.4th

963 (D.C. Cir. 2026) and is reproduced in the Petition

Appendix (Pet. App.) at Pet. App. 1a–45a. Relevant

excerpts of the United States Environmental

Protection Agency’s (EPA’s) Final Rule titled

“Reconsideration of the National Ambient Air Quality

Standards for Particulate Matter,” 89 Fed. Reg.

16,202 (Mar. 6, 2024) (Rule), are reproduced at Pet.

App. 46a-465a.

JURISDICTION

The D.C. Circuit’s decision was entered on June

26, 2026. The jurisdiction of this Court is invoked

under 28 U.S.C. § 1254(1).

STATUTORY PROVISIONS INVOLVED

42 U.S.C. § 7408 provides, in relevant part:

(a) Air pollutant list; publication and revision

by Administrator, issuance of air quality

criteria for air pollutants

(1) …

(2) The Administrator shall issue air quality

criteria for an air pollutant within 12

months after he has included such pollutant

in a list under paragraph (1). Air quality

criteria for an air pollutant shall accurately

reflect the latest scientific knowledge useful

in indicating the kind and extent of all

identifiable effects on public health or

welfare which may be expected from the

presence of such pollutant in the ambient

air, in varying quantities ....

criteria or information

The Administrator shall from time to time

review, and, as appropriate, modify, and

reissue any criteria or information on control

techniques issued pursuant to this section ....

42 U.S.C. § 7409 provides, in relevant part:

(b) Protection of public health and welfare

(1) National primary ambient air quality

standards, prescribed under subsection (a)

shall be ambient air quality standards the

attainment and maintenance of which in the

judgment of the Administrator, based on

such criteria and allowing an adequate

margin of safety, are requisite to protect the

public health. Such primary standards may

be revised in the same manner as

promulgated.

(2) …

…

(d) Review and revision of criteria and

standards; independent scientific review

committee; appointment; advisory functions

(1) Not later than December 31, 1980, and

at five-year intervals thereafter, the

Administrator shall complete a thorough

review of the criteria published under

section 7408 of this title and the national

ambient air quality standards promulgated

under this section and shall make such

revisions in such criteria and standards and

promulgate such new standards as may be

appropriate in accordance with section 7408

of this title and subsection (b) of this section.

The Administrator may review and revise

criteria or promulgate new standards

earlier or more frequently than required

under this paragraph.

42 U.S.C. § 7409 is reproduced at Pet. App. 466a–

469a.

INTRODUCTION

For more than four decades, EPA never revised a

National Ambient Air Quality Standard (NAAQS)

without thoroughly reviewing the latest underlying

science, as required by the Clean Air Act (CAA). But

in the rule at issue, EPA asserted for the first time

that it could bypass that requirement if revising a

NAAQS off-cycle—i.e., between the five-year reviews

required by the statute. EPA has since abandoned

that position and conceded the rule was ultra vires.

Yet the D.C. Circuit upheld it anyway. And the court

did so by relying on a statutory provision that EPA

never invoked (and even disavowed) as authority for

its action, and that does not excuse the thoroughreview requirement in any event. If allowed to stand,

the court’s decision gives EPA the remarkable

discretion to circumvent an important substantive

safeguard. It also prohibits EPA from considering

whether costs, disruptions, and other consequences

might militate against exercising such discretion.

Few regulatory actions under the CAA are more

far-reaching than a NAAQS revision, which adjusts

the nationally applicable numeric limit on the air

concentration of a particular pollutant. Air pollution

is generated by virtually every sector of the economy,

including transportation, agriculture, manufacturing,

energy production, and residential heating.

Accordingly, a single change to a NAAQS can impose

enormous regulatory costs. It can push areas across

the country out of compliance; force states to devise

multiple, stringent, and complex state regulatory

regimes (State Implementation Plans or SIPs); and

immediately impose stricter permitting requirements

for all manner of construction in much of the country.

These consequences are particularly significant for

the NAAQS at issue, which concerns fine particulate

matter (PM2.5). A growing majority of PM2.5 emissions

originates from diffuse and episodic sources that are

inherently difficult for States to control, such as

wildfires, road dust, agricultural activities, and

residential wood-burning. As a result, more stringent

standards can be nearly impossible to meet.

Congress

imposed

the

thorough-review

requirement in 1977 precisely because of these stakes.

It added section 109(d)(1) of the CAA not just as an

“action-forcing” device—requiring EPA to act on a

five-year cycle—as the decision below held. The

provision is also a substantive safeguard, requiring

EPA to complete a “thorough review” of the latest,

underlying science before revising a NAAQS. Further

confirming that mandate, Congress amended section

109(d) at the same time to require an independent

scientific committee to advise EPA on the NAAQS.

In the rule at issue, EPA skipped that substantive

safeguard. In December 2020, EPA completed an oncycle thorough review and decided not to change the

primary annual standard for PM2.5. But after a new

administration took office, EPA launched an off-cycle

“reconsideration” that it acknowledged did not include

a “thorough review”—i.e., a comprehensive evaluation

of all peer-reviewed literature on the pollutant

published since the last review. Instead, EPA

reviewed a limited selection of additional studies and

issued a rule that lowered the PM2.5 standard by 25%,

nearing background concentrations that States have

limited ability to control. It was—the agency also

acknowledged—the first time EPA had ever revised a

NAAQS without completing a thorough review.

In its rulemaking to lower the standard, EPA also

refused to consider the costs or other consequences of

its discretionary action. EPA explained that in its

view, all such decisions relating to NAAQS revisions

are subject to Whitman v. American Trucking Ass’ns,

531 U.S. 457 (2001), which prohibits EPA from

considering costs when selecting the appropriate level

for a NAAQS under section 109(b).

The D.C. Circuit’s decision upholding EPA’s

unprecedented claim of regulatory power is wrong for

two independent reasons, each of which warrants this

Court’s review.

First, the court of appeals erred in holding that

EPA may skip the thorough-review requirement when

it performs off-cycle revisions. Among other mistakes,

the court selectively applied the omitted-case canon—

the principle that a statutory omission is presumed

deliberate. Specifically, the court held that the second

sentence in section 109(d)(1) did not refer back to the

word “thorough” from the first sentence, yet then held

it does refer back to other language in the first

sentence needed to sustain the court’s conclusion. In

addition, the court ultimately grounded EPA’s

revision authority in a separate statutory provision—

section 109(b)—that the agency never invoked as

authority for its action during the rulemaking and

expressly disavowed during litigation.

Second, the court of appeals erred in holding that

EPA must not consider costs when choosing to

exercise its discretionary off-cycle authority—

ignoring this Court’s precedents on reasoned agency

decision-making and extending Whitman far beyond

its holding and reasoning.

Review is needed now. NAAQS challenges lie

exclusively in the D.C. Circuit, so no circuit split over

these questions of statutory interpretation will ever

develop. And the only other means of reversing the

PM2.5 standard at issue—further rulemaking—could

be substantially hindered by the CAA’s antibacksliding provision. That provision, which impedes

EPA from lowering a NAAQS if certain conditions are

met, looms ever larger as implementation of the

standard continues apace. All. of Nurses for Healthy

Env’ts v. Zeldin, No. 26-cv-03118, 2026 WL 2078145

(N.D. Cal. July 17, 2026) (ordering EPA, by February

2027, to issue final area designations concerning

attainment of the PM2.5 standard at issue).

The Court should grant certiorari.

STATEMENT

Statutory and regulatory background

The cascading consequences of a

National

Ambient

Air

Quality

Standard (NAAQS)

The NAAQS set numeric limits on the

concentration of “listed” pollutants (known as

“criteria” pollutants) in outdoor air. Under section

108(a)(1), EPA must list pollutants that endanger

public health or welfare and stem from “numerous or

diverse” sources, whether mobile or stationary. 42

U.S.C. § 7408(a)(1)(A)–(B). Since Congress passed the

CAA in 1970, EPA has listed six pollutants.

Setting an initial NAAQS

When initially promulgated, a NAAQS becomes

the organizing principle for a comprehensive

regulatory system, creating a domino effect of State

obligations, regulation, and industry compliance

requirements. See, e.g., Lisa Heinzerling, The Clean

Air Act and the Constitution, 20 ST. LOUIS U. PUB. L.

REV.121, 121 (2001) (NAAQS “form the centerpiece of

… this country’s single most important environmental

program”).

To begin, all fifty States must classify all areas

within their territory as in “attainment” (meeting the

standard), “nonattainment” (not meeting it), or

“unclassifiable.” 42 U.S.C. § 7407(d)(1)(A). States

must propose designations within one year of

promulgation of a NAAQS. Ibid. This requires States

to analyze emissions, air quality, and other data,

which can, for each State, cost seven figures and

require hundreds of staff hours. State Pet’rs’ Opening

Br. 18; id. Addendum (Add.) 100a, Kentucky v. EPA,

179 F.4th 963 (D.C. Cir. 2026) (No. 24-1050). EPA

must then approve or revise those designations within

two years of promulgation—or three, if EPA grants

itself

one-year

extension.

U.S.C.

§ 7407(d)(1)(B)(i).

States then generate one or more SIPs:

comprehensive regulatory regimes comprising

emission limits, permitting requirements, compliance

schedules, monitoring requirements, and other

control measures to implement and enforce the

NAAQS. Id. § 7407(a); see id. § 7410(a)(1), (a)(2)(A).

SIPs also include “good neighbor” provisions to

prevent States from materially interfering with

NAAQS attainment in States downwind. Id.

§ 7410(a)(2)(D); Ohio v. EPA, 603 U.S. 279, 283 (2024).

SIPs require considerable expense, coordination, and

outreach to develop, and then cost each State millions

more annually to carry out. State Pet’rs’ Opening Br.

Add. 63a,78a–79a.

SIPs impose compliance obligations on any “source

of an air pollutant.” 42 U.S.C. § 7602(z). That

effectively includes the entire U.S. economy—from

power plants and factories to construction sites,

agricultural operations, transportation, commercial

operations, and even residential heating and

prescribed fires. U.S. Chamber of Commerce,

Comments on Proposed Rule, U.S. Environmental

Protection Agency: Reconsideration of the National

Ambient Air Quality Standards for Particulate

Matter, 88 Fed. Reg. 5558-5719 (Jan. 27, 2023) at 3, 5

(Mar. 28, 2023), EPA-HQ-OAR-2015-0072-2428.

In nonattainment areas, SIPs require regulated

parties to do whatever is “necessary or appropriate to

provide for attainment.” 42 U.S.C. §§ 7510a(a)(2),

7502(c)(6). Existing sources must implement

“reasonably available [emission] control measures as

expeditiously as practicable.” Id. § 7502(c)(1). Such

measures include expensive control equipment, such

as high-efficiency cyclones. Industry Opening Br. Add.

216, Kentucky v. EPA, 179 F.4th 963 (D.C. Cir. 2026)

(No. 24-1050).

Revising a NAAQS

Revising an already existing NAAQS sets in

motion its own vast array of consequences.

For starters, a revision instantly tightens preconstruction permitting in areas that attained the

prior standard (or were unclassifiable). Applicants

there must show, through sophisticated air modeling,

that any major new source or modification “will not

cause, or contribute to, air pollution in excess of” the

revised standard. 42 U.S.C. § 7475(a)(3). This may

require significant redesign of planned projects—for

example, spending $20 million re-engineering stacks

on paper machines, or spending millions paving what

were planned to be gravel roads, Industry Opening Br.

Add. 232. What is more, the revised NAAQS has been

held to apply immediately not just to new permit

applications, but to pending ones too. Murray Energy

Corp. v. EPA, 936 F.3d 597, 624–25 (D.C. Cir. 2019)

(per curiam).

All fifty States then redo their regulatory regimes.

They must again submit comprehensive area

classifications, which can take EPA two to three years

to approve or revise. 42 U.S.C. § 7407(d)(1)(A),

(d)(1)(B)(i). And then they develop new SIPs, id.

§ 7410(a)(1), which require the same extensive

coordination and outreach as when initially

developed, State Pet’rs’ Opening Br. Add. 63a.

Revisions particularly affect areas that were not

attaining the prior standard. New sources there must

meet the “lowest achievable emission rate”—generally

the more stringent of (a) the tightest limit in any

State’s new plan and (b) the greatest reduction

“achieved in practice” by the same class or category of

source. 42 U.S.C. §§ 7501(3), 7503(a)(2). For example,

if California sets an aggressive new emissions limit,

or an industry there achieves an even more aggressive

limit in practice, that limit will apply to all

nonattainment areas in all 49 other States.

Finally, the CAA’s anti-backsliding provision

provides that if EPA relaxes a standard after certain

events have occurred, areas that had not attained the

prior standard must retain “controls which are not

less stringent” than what applied before. Id. § 7502(e).

This impedes EPA’s ability to relax a NAAQS after a

certain point in time.

Requirements for promulgating and

revising a NAAQS

Given the consequences of setting or revising a

NAAQS, the CAA prescribes specific requirements

that EPA must follow.

Before setting a standard for the first time, EPA

must issue “air quality criteria” for the pollutant

under section 108. Id. § 7408(a)–(b). The criteria must

“accurately reflect the latest scientific knowledge”

regarding the impacts of the pollutant on public

health or welfare. Id. § 7408(a)(2).

After issuing criteria, EPA promulgates the initial

NAAQS. Id. § 7409, Pet. App. 466a. These initial

NAAQS must be set to levels which “in the judgment

of the Administrator, based on such criteria and

allowing an adequate margin of safety, are requisite

to protect the public health.” Id. § 7409(b)(1), Pet.

App. 467a. And before doing so, EPA must provide

notice and an opportunity for comment. Id. § 7409(a),

Pet. App. 466a.

The CAA also specifies how EPA should revise

NAAQS. Section 109(b)(1) instructs that NAAQS

“may be revised in the same manner as promulgated.”

Id. § 7409(b)(1), Pet. App. 467a. Section 109(d)(1)

requires that NAAQS revisions follow “a “thorough

review of the criteria … and … standards.” Id.

§ 7409(d)(1), Pet. App. 468a. And a congressionally

mandated independent Clean Air Scientific Advisory

Committee (CASAC) must “recommend to the

Administrator” revisions to criteria and standards. Id.

§ 7409(d)(2)(A)–(B), Pet. App. 468a–469a.

The “thorough review” required by section

109(d)(1) is comprehensive, given that the criteria

under review must reflect “the latest scientific

knowledge” on “all identifiable effects on public health

or welfare,” Id. § 7408(a)(2). Historically, EPA carried

out this review by preparing an Integrated Science

Assessment—a comprehensive evaluation of all peerreviewed literature on the pollutant published since

the last review cycle. Decl. of Aaron Szabo ¶¶ 36, 38,

(Nov. 24, 2025), Kentucky v. EPA, 179 F.4th 963 (D.C.

Cir. 2026) (No. 24-1050) (Szabo Decl.), Pet. App. 533a–

534a; 89 Fed. Reg. at 16,207–08, Pet. App. 71a–74a.

EPA has also traditionally prepared a Policy

Assessment evaluating whether existing standards

remain adequate in light of that science. See EPA,

EPA-452/R-22-004, Policy Assessment for the

Reconsideration of the National Ambient Air Quality

Standards for Particulate Matter 1–2 (May 2022),

EPA-HQ-OAR-2015-0072-1584. Both documents are

reviewed by the CASAC. Szabo Decl. ¶ 11, Pet. App.

508a.

Section 109(d)(1) also speaks to the timing of

reviews and revisions. Id. § 7409(d)(1), Pet. App. 468a.

The first sentence requires reviews and any

appropriate revisions at “five-year intervals,” i.e. oncycle. Id. The second permits what is “required under

this paragraph” to occur between those intervals, i.e.

off-cycle:

[A]t five-year intervals … , the

Administrator shall complete a thorough

review of the criteria … and … standards

… and shall make such revisions in such

criteria and standards and promulgate

such new standards as may be

appropriate in accordance with section

7408 of this title and subsection (b) of

this section. The Administrator may

review and revise criteria or promulgate

new standards earlier or more frequently

than required under this paragraph.

Id.

II.

The proceedings below

The revised PM2.5 standard

The NAAQS at issue concerns PM2.5—liquid or

solid particles up to 2.5 micrometers (μm) suspended

in air. 89 Fed. Reg. at 16,213–14, Pet. App. 103a.

These come from many manmade sources, including

power plants, manufacturing facilities, construction

equipment, agricultural operations, and vehicle fuel

combustion and brakes. Ibid. They also come from

natural sources, including wildfires, pollen, and sea

spray. 85 Fed. Reg. 82,684, 82,692 n.23 (Dec. 18,

2020).

EPA promulgated the initial NAAQS for PM2.5 in

1997, setting the standard at 15.0 micrograms per

cubic meter of air (μg/m3) after an on-cycle thorough

review. 89 Fed. Reg. at 16,207, Pet. App. 71a. In 2012,

EPA lowered the annual standard to 12.0 μg/m3, again

following an on-cycle thorough review. Id. at 16,208,

Pet. App. 77a.

In 2020, EPA completed its most recent on-cycle

thorough review and decided not to revise the primary

annual standard. Id. at 16,209, Pet. App. 81a–82a.

But several months later, in June 2021, a new

administration announced that it would revisit the

2020 decision.2 EPA then issued a proposed rule, 88

Fed. Reg. 5558, 5560 (Jan. 27, 2023), which it later

finalized in 2024. The final rule lowered the primary

annual PM2.5 standard by 25%—from 12.0 μg/m3 to 9.0

μg/m3. 89 Fed. Reg. at 16,202, Pet. App. 46a.

When lowering this standard, EPA conceded that

it had not conducted a “thorough review” of the

criteria and standards for PM2.5. Instead of preparing

a new Integrated Science Assessment—the

comprehensive evaluation of all peer-reviewed

literature used in the 2020 thorough review—EPA

prepared a “Supplement” covering newer select

studies. 89 Fed. Reg. at 16,211–13, Pet. App. 91a–

102a; Szabo Decl. ¶¶ 36, 38, Pet. App. 533a–534a, Pet.

App. 536a–537a. It then “partially reopen[ed]” the

criteria for “provisional consideration” of those select

studies, deferring “full[]” assessment of the studies to

“a more rigorous review process” during the next oncycle review. 89 Fed. Reg. at 16,211, 16,213, Pet. App.

See Press Release, EPA, EPA to Reexamine Health

Standards for Harmful Soot that Previous Administration Left

Unchanged (June 10, 2021), https://tinyurl.com/2uvxmymj (last

visited Aug. 26, 2026).

88a, Pet. App. 102a; EPA, Response to Comments

121–22 (undated), EPA-HQ-OAR-2015-0072-6025

(RTC), Pet. App. 486a–488a. EPA acknowledged that

this doubly abbreviated process—“provisional

consideration” of only some new studies—did “not

itself satisfy EPA’s obligation to periodically complete

a thorough review of the air quality criteria.” RTC

121, Pet. App. 485a.

The agency had never revised a NAAQS without

completing a thorough review. Szabo Decl. ¶¶ 36, 38,

Pet. App. 533a–534a, Pet. App. 536a–537a; see

also Final Br. for U.S. Environmental Protection

Agency 79, Kentucky v. EPA, 179 F.4th 963 (D.C. Cir.

2026) (No. 24-1050) (EPA Resp. Br.) (agreeing that

“‘EPA has never revised a NAAQS after a voluntary

[off-cycle] reconsideration’”); infra 39 n.4. In doing so

for the first time, EPA acknowledged that “the first

sentence of section 109(d)(1) imposes a duty … to

‘complete a thorough review’” before revising a

NAAQS. RTC 121, Pet. App. 486a. But, EPA

explained, “a careful reading” revealed “that the last

sentence” authorized EPA to revise a NAAQS without

this “thorough review” so long as EPA did so off-cycle.

Ibid.

EPA described this second sentence as providing

“additional authority, independent of” the first—and

that it specifically “authorizes” EPA to revise the

NAAQS off-cycle without a “thorough review.” Ibid. At

no point did EPA invoke section 109(b) as independent

authority

bypass

the

thorough-review

requirement. See Szabo Decl. ¶ 40, Pet. App. 538a.

EPA also refused to consider the costs or other

consequences of initiating a wholly voluntary,

discretionary off-cycle review. RTC 120, Pet. App.

483a. Here, EPA reasoned that section 109(b) requires

any NAAQS revision to be “requisite to protect the

public

health,”

and

that

this

standard

“unambiguously bars cost considerations from the

NAAQS-setting process.” RTC 118, 120, Pet. App.

477a–478a, Pet. App. 481a (discussing Whitman, 531

U.S. at 471).

The D.C. Circuit litigation

Numerous parties filed petitions for review in the

D.C. Circuit, which has exclusive jurisdiction over

challenges to NAAQS. 42 U.S.C. § 7607(b)(1).

Petitioners argued that EPA exceeded its authority by

revising a NAAQS without a thorough review and

without considering the costs of undertaking a

discretionary off-cycle review. Industry Pet’rs’

Opening Br. 32–42; Industry Pet’rs’ Reply Br. 4–22,

Kentucky v. EPA, 179 F.4th 963 (D.C. Cir. 2026) (No.

24-1050).

EPA defended the Rule by again claiming that the

second sentence of section 109(d)(1) confers “separate,

discretionary authority” to revise NAAQS off-cycle

without a “‘thorough review.’” EPA Resp. Br. 45. EPA

did not rely on section 109(b) as authority for this

claimed power. EPA also argued that it could not

consider costs and attainability under Whitman—a

case addressing EPA’s selection of a new NAAQS level

after a mandatory on-cycle review, 531 U.S. 457. EPA

Resp. Br. 50–52.

At oral argument, a member of the panel proposed

a different theory: that EPA’s off-cycle revision

authority stemmed not from section 109(d)(1), but

from section 109(b), which in the judge’s view

contained no “thorough review” requirement. Tr. of

Oral Arg. at 8–11, Kentucky v. EPA, 179 F.4th 963

(D.C. Cir. 2026) (No. 24-1050) (Tr. of Oral Arg.).

Petitioners responded that this theory was foreclosed

under the party-presentation principle and SEC v.

Chenery Corp., 318 U.S. 80, 88 (1943), and was

mistaken anyway. Tr. of Oral Arg. at 12. State

Intervenors embraced the panel’s theory, while EPA’s

counsel was more circumspect—responding that the

court “could go to (b)(1),” id., but reiterating that the

Rule was “also properly invoking (d)(1),” id. at 64:6–8,

83.

After oral argument, a new administration took

office. EPA then confessed error and moved to vacate

the Rule. EPA first argued that the Rule should be

vacated because it was not based on a “thorough

review.” In doing so, it confirmed that “[section 109(b)]

was not the basis asserted in the Rule, and EPA has

never attempted to bypass section 109(d)(1) by relying

solely on section 109(b).” Resp’ts’ Mot. For Vacatur 2,

Kentucky v. EPA, 179 F.4th 963 (D.C. Cir. 2026) (No.

24-1050) (Mot. To Vacate); Szabo Decl. ¶ 40, Pet. App.

538a (“To date, including in the 2024 Rule, the EPA

never asserted that 109(b) alone authorized revising

the NAAQS without also referencing 109(d).”). EPA

also argued that it had improperly failed to consider

costs before deciding to review the NAAQS off-cycle.

Mot. to Vacate 10–21.

The D.C. Circuit denied EPA’s motion to vacate

and the petitions for review, upholding the Rule. Pet.

App. 9a–10a. On the issue of “thorough review,” the

court embraced the approach it had suggested for the

first time at argument. Pet. App. 22a–30a. Under that

theory, the second sentence of 109(d)(1) merely

“clarif[ies]” that “nothing in § 7409(d)(1) displaces the

Administrator’s revision authority in § 7409(b).” Pet.

App. 24a. Because the court did not understand

section 109(b) to require a thorough review, it

concluded that EPA acted within its off-cycle revision

authority. Pet. App. 22a–24a.

The court did not address petitioners’ partypresentation objection, but did briefly discuss Chenery

in a footnote. Pet. App. 24a n.5. It first reasoned that

Chenery is “inapplicable” to questions of “‘statutory

construction.’” Ibid. (citation omitted). It then

reasoned that EPA satisfied Chenery anyway by

mentioning section 109(b) in the statement discussed

earlier (supra p. 17 (discussing RTC 120, Pet. App.

483a)), in which EPA explained why it could not

consider costs. Ibid. (citing RTC 120, Pet. App. 483a).

The court next held that EPA need not consider

costs or attainability when deciding whether to

undertake a discretionary off-cycle review. Pet. App.

33a–39a. In doing so, it, too, relied on Whitman. 531

U.S. at 462–63. The court acknowledged that D.C.

Circuit precedent invoking Whitman “spoke of

‘formulating the NAAQS,’” “not the anterior decision”

whether to review them (which exists only off-cycle).

Pet. App. 37a. But the court did “not see” how that

precedent “would permit the Administrator to

consider costs at either stage.” Ibid.

Following the decision below, a district court

ordered EPA to complete area designations under the

9.0 μg/m3 standard by February 2027. All. of Nurses

for Healthy Env’ts, 2026 WL 2078145.

REASONS FOR GRANTING THE PETITION

The decision below presents two important

questions about EPA’s authority to revise a NAAQS.

If that decision stands, EPA may now revise any

standard for any criteria pollutant, without a

“thorough review” of the criteria, and while ignoring

cost—so long as it acts off-cycle.

This Court’s intervention is needed now, as this

Court is likely the only path to fully effective relief.

These purely legal questions fall within the D.C.

Circuit’s exclusive jurisdiction, 42 U.S.C. § 7607(b)(1),

and were squarely raised and decided below. And as

implementation proceeds, the CAA’s anti-backsliding

provision increasingly threatens to impede agency

correction of the PM2.5 standard at issue—regardless

of what a later review concludes, see supra p. 11.

The D.C. Circuit erred by excusing EPA

from the Clean Air Act’s “thorough

review” requirement.

The D.C. Circuit erred in concluding that EPA may

revise a NAAQS without a “thorough review,” merely

because it acts off-cycle. It did so by improperly

injecting its own theory of EPA’s revision authority

based on a separate statutory provision EPA never

invoked for that purpose. That theory was also wrong

on the merits.

Section 109(d)(1) requires a thorough

review for all NAAQS revisions,

whether on- or off-cycle.

Statutory interpretation “begins with the

text,” Ross v. Blake, 578 U.S. 632, 638 (2016),

applying “the traditional tools of statutory

construction” to determine the “best reading.” Loper

Bright Enters. v. Raimondo, 603 U.S. 369, 400, 403

(2024). Here, the best reading is that section 109(d)(1)

requires a “thorough review” for all NAAQS revisions.

Since 1977, section 109(d)(1) has imposed

procedural and substantive requirements on all

NAAQS revisions. Its first sentence addresses both. It

requires EPA to review criteria and standards at “fiveyear intervals.” And it also imposes crucial

substantive safeguards—by requiring EPA’s review to

be “thorough” and mandating that any revisions be

“appropriate” and “in accordance with section [108]

and [section 109(b)].” 42 U.S.C. § 7409(d)(1), Pet. App.

468a.

The second sentence addresses timing alone. It

allows EPA to do “earlier or more frequently” what the

first sentence otherwise requires:

[A]t five-year intervals … , the

Administrator shall complete a thorough

review of the criteria … and … standards

… and shall make such revisions in such

criteria and standards and promulgate

such new standards as may be

appropriate in accordance with section

7408 of this title and subsection (b) of

this section. The Administrator may

review and revise criteria or promulgate

new standards earlier or more frequently

than required under this paragraph.

Ibid. (emphasis added). This sentence changes none of

the preceding requirements.

This reading of the second sentence is bolstered by

its reference to what is “required under this

paragraph.” The only substantive requirements in

“this paragraph” are in the first sentence: EPA must

“complete a thorough review,” then make “revisions,”

or “promulgate” new standards, as “appropriate” and

“in accordance with” sections 108 and 109(b). The

second sentence references those same three actions

(“review,” “revise,” “promulgate”). Ibid. Together with

the reference to “under this paragraph,” that

symmetry confirms that the second sentence refers to

the same substantive requirements found in the first.

The second sentence does not repeat every word of

the first. It does not say “thorough,” does not refer to

revising standards, and does not reiterate that all

standards must be appropriate or in accordance with

sections 108 and 109(b). But that is because the

sentence does not set forth requirements; it addresses

the timing for doing what already is “required under

this paragraph.”

Courts “‘must not be guided by a single sentence,’”

but instead “‘look to the provisions of the whole law.’”

Richards v. United States, 369 U.S. 1, 11 (1962)

(citation omitted). And a term is often “given more

precise content by the neighboring words with which

it is associated.” United States v. Williams, 553 U.S.

285, 294 (2008). Here, that context shows that the

second sentence uses a “shorthand” reference, Exxon

Corp. v. Hunt, 475 U.S. 355, 369 (1986)—i.e., a concise

reference to an otherwise complex subject. If this

second sentence had repeated all elements in the first,

it would be much more complex:

The Administrator may review and

revise criteria or promulgate new

standards complete a thorough review of

the criteria published under section 7408

of this title and the national ambient air

quality standards promulgated under

this section, and make such revisions in

such criteria and standards and

promulgate new standards as may be

appropriate in accordance with section

7408 of this title and subsection (b) of

this section, earlier or more frequently

than required under this paragraph.

Such shorthand references appear throughout the law

to simplify far less complex phrases. See, e.g., 18

U.S.C. § 1084(a) (using “bets or wagers” to refer back

to “bets or wagers on any sporting event or contest”);

17 U.S.C. § 102(a) (using “[w]orks of authorship” to

refer back to “original works of authorship”).

Reading the second sentence’s omissions as

exceptions to the requirements of the first sentence

also would make little sense. The second sentence

omits not only the word “thorough,” but also any

language authorizing EPA to revise standards. See 42

U.S.C. § 7409(d)(1), Pet. App. 468a (“The

Administrator may review and revise criteria or

promulgate new standards earlier or more frequently

than required under this paragraph.”) (emphasis

added). If the sentence is not a shorthand reference,

and the “omitted-case” canon applies equally to all

missing words, then EPA has no authority to revise

standards off-cycle at all. ANTONIN SCALIA & BRYAN A.

GARNER, READING LAW: THE INTERPRETATION OF

LEGAL TEXTS 93 (2012). The better interpretation is

that the sentence uses shorthand, making the

omissions immaterial.

That interpretation also best fits the statutory

structure. The CAA uniformly defines what a NAAQS

is—and what it must rest on. Under section 108, all

air quality criteria must “accurately reflect the latest

scientific knowledge” concerning “all identifiable

effects on public health or welfare.” 42 U.S.C.

§ 7408(a)(2). And under section 109(b), all NAAQS

must be “based on such criteria.” Id. § 7409(b)(1), Pet.

App. 467a. Indeed, that is why NAAQS pollutants are

called “criteria” pollutants. As this Court has

explained, the statute “at a minimum requires that

‘[f]or a discrete set of pollutants and based on

published air quality criteria that reflect the latest

scientific knowledge, [the] EPA must establish

uniform national standards.’” Whitman, 531 U.S. at

473 (emphasis added, citation omitted). If all NAAQS

must rest on criteria reflecting the latest science, EPA

cannot escape that obligation by acting between

review cycles.

The D.C. Circuit’s contrary theory of

statutory authority was improper and

incorrect.

Petitioners have the best reading of section

109(d)(1), and the D.C. Circuit erred by holding

otherwise. Before reaching that provision, however,

the court erred by injecting its own theory into the

case.

The D.C. Circuit violated the

principle of party presentation.

“‘In our adversarial system of adjudication, we

follow the principle of party presentation.’” Clark v.

Sweeney, 607 U.S. 7, 9 (2025) (per curiam) (quoting

United States v. Sineneng-Smith, 590 U.S. 371, 375

(2020)). That principle requires that “the parties …

frame the issues for decision,” while the court serves

as neutral arbiter of matters the parties present.

Margolin v. Nat’l Ass’n of Immigr. Judges, 146 S. Ct.

1285, 1288 (2026) (per curiam) (internal quotation

marks and citation omitted).

The D.C. Circuit violated that principle. During

litigation and rulemaking, the parties offered two

competing readings of section 109(d)(1). Petitioners

read section 109(d)(1) to require a thorough review for

any revision of the NAAQS, whether on-cycle or off.

See supra Section I. EPA argued that the second

sentence independently authorized off-cycle revision

without a thorough review. See supra pp. 17–18.

The D.C. Circuit rejected both readings and

injected its own theory at oral argument that section

109(b) authorized EPA to revise the NAAQS off-cycle.

Pet. App. 24a. Under this third approach, the first

sentence of section 109(d)(1) limits revision authority

under section 109(b), but only for on-cycle revisions.

The second sentence then neither confers authority

nor modifies the prior sentence’s timing requirement.

Rather, it merely “clarif[ies]” that the on-cycle review

process does not otherwise “displace[] the

Administrator’s revision authority in § [109(b)].” Ibid.

But EPA affirmatively disclaimed this theory—

explaining that section 109(b) “was not the basis

asserted in the Rule” and that “EPA has never

attempted to bypass section 109(d)(1) by relying solely

on section 109(b).” Mot. to Vacate 2. EPA explained

that “[t]o view section 109(b) that way contradicts

decades of agency practice,” id. at 2–3, and that it has

“never asserted that 109(b) alone authorized revising

the NAAQS,” Szabo Decl. ¶ 40, Pet. App. 538a.

Despite that, the D.C. Circuit embraced its own theory

and held that section 109(b) authorized the challenged

Rule.

The D.C. Circuit’s opinion nowhere addressed

petitioners’ objection that its approach violated the

party-presentation principle. It did mention that

Intervenors had ultimately embraced the section

109(b)(1) theory after the court proposed it. Pet. App.

20a. But the same occurred in Sineneng-Smith, where

a party “adopted” and “rode with [a new] argument

suggested by the panel.” 590 U.S. at 379. That didn’t

“justif[y] the panel’s takeover of the appeal,” id., so

this Court vacated the judgment. The same is

warranted here.

This Court has recently reversed several other

circuit court decisions for ignoring the party

presentation rule, and it should likewise do so here.

See, e.g., id. at 380; Margolin, 146 S. Ct. at 1288

(reversing and noting a recent similar reversal);

Clark, 607 U.S. at 9. And because the lower court

already rejected the ground EPA did rely on below,

this violation requires vacatur of the Rule. See infra

pp. 30–31.

The D.C. Circuit violated Chenery.

The decision below violated Chenery, too. During

rulemaking, EPA never relied on section 109(b) as the

source of its off-cycle revision. The D.C. Circuit’s

reliance on that provision was thus doubly improper.

The “now-bedrock” Chenery doctrine prohibits

courts from upholding agency action “on an

alternative ground raised for the first time in

litigation.” FDA v. Wages & White Lion Invs., LLC,

604 U.S. 542, 587 (2025). This rule “serves important

values of administrative law,” by promoting “‘agency

accountability,’” allowing regulated parties to

“respond fully” to a proposed action, and “instill[ing]

confidence that the reasons given are not simply

‘convenient litigating position[s].’” Dep’t of Homeland

Sec. v. Regents of the Univ. of California, 591 U.S. 1,

22–23 (2020) (citations omitted). It also prevents

courts from “‘intrud[ing] upon the domain which

Congress … exclusively entrusted to [the]

administrative agency.’” Wages & White Lion, 604

U.S. at 587 (quoting Chenery, 318 U.S. at 88).

The D.C. Circuit violated Chenery. EPA concedes

that it “never attempted to bypass section 109(d)(1)”

during rulemaking “by relying solely on section

109(b).” Supra pp. 26–27 (quoting Mot. to Vacate 2).

Instead, EPA repeatedly claimed that the second

sentence of section 109(d)(1) “specifically authorizes”

off-cycle revisions. See supra pp. 16–17 (quoting RTC

121, Pet. App. 485a). Accordingly, the D.C. Circuit’s

new theory based on section 109(b) was off limits.

The D.C. Circuit asserted in a footnote that

Chenery did not apply for two reasons. Pet. App. 24a

n.5. Neither is convincing.

First, the D.C. Circuit held that an exception to

Chenery applies “‘when the question presented [is] one

of statutory construction,’” Ibid. (citation omitted),

pointing to Loper Bright, Tr. of Oral Arg. at 50–51.

But Loper Bright directs courts to decide what a

particular provision means. 603 U.S. at 394. It does

not allow courts to decide which provision an agency

should have invoked as authority for its action. In

holding otherwise, the D.C. Circuit thwarted the core

purposes of Chenery. See supra p. 28. It also split with

two other circuits. See Apogee Coal Co. v. Off. of

Workers’ Comp. Programs, 113 F.4th 751, 762 (7th

Cir. 2024) (concluding, after Loper Bright, that

Chenery “prohibits [courts] from scouring [statutes]

for bases” of an agency’s authority); Bank of Am., N.A.

v. F.D.I.C., 244 F.3d 1309, 1321 (11th Cir. 2001)

(“[e]ven if other statutory provisions could support the

[agency’s] asserted authority,” courts “cannot supply

grounds … that were not invoked by the [agency]

below.”) (quotation marks and citation omitted).

Second, the D.C. Circuit said that EPA did rely on

section 109(b), citing a single comment by EPA in the

extensive rulemaking record. Pet. App. 24a. But

context shows that this comment invoked section

109(b) as a restriction on EPA’s authority, not a

source. Addressing whether EPA was “required to

consider costs,” EPA said:

The EPA understands [section 109(b)] to

authorize the Administrator to revise the

NAAQS and to require that every

NAAQS revision be subject to the same

basic requirements under section 109

(and Whitman)—the standards must be

based on the air quality criteria and

must be requisite to protect the public

health for primary standards.

RTC at 120, Pet. App. 482a.

That is not enough. Under Chenery, what matters

is “the grounds upon which the agency acted.” 318

U.S. at 95 (emphasis added). And here, the “grounds”

for EPA’s action was section 109(d)(1). RTC 121–22,

Pet. App. 486a–487a.

***

The D.C. Circuit’s violations of the partypresentation

principle

and

Chenery

each

independently require reversal and vacatur of the

Rule. See Sineneng-Smith, 590 U.S. at 380 (party

presentation); Regents, 591 U.S. at 21 (Chenery). In

the decision below, the court rejected the only

statutory ground EPA invoked during rulemaking.

Pet. App. 24a–25a (holding that the second sentence

of section 109(d)(1) merely “clarif[ies]” that “nothing

in [section 109(d)(1)] displaces the Administrator’s

revision authority”). And the court cannot rely on

section 109(b). With no surviving statutory basis,

nothing sustains the Rule. Indeed, EPA concedes

“there is no serious possibility” it would adopt the

same approach on remand. Mot. to Vacate 22.

The D.C. Circuit’s theory was wrong

on the merits.

Even setting aside that the D.C. Circuit should not

have relied on section 109(b), the D.C. Circuit’s

reading of that provision was wrong for two

independent reasons. First, section 109(b) does not

provide revision authority at all. And second, even if

it did, that authority is limited by section 109(d)(1).

Section 109(b) does not confer

revision authority.

The D.C. Circuit erroneously read the second

sentence of section 109(b)(1) to confer revision

authority. That sentence has always exclusively

addressed procedure—providing that NAAQS “may

be revised in the same manner as promulgated.” 42

U.S.C. § 7409(b)(1), Pet. App. 467a (emphasis added).

“Manner” means “a way or method in which

something is done or happens.” WEBSTER’S NEW

WORLD DICTIONARY, SECOND COLLEGE EDITION (1972).

Here, the “manner” in which NAAQS are

“promulgated” is prescribed by section 109(a) (titled

“Promulgation”), which requires notice and an

opportunity for “comments.” 42 U.S.C. § 7409(a), Pet.

App. 466a. Accordingly, section 109(b) only requires

notice and comment for NAAQS revisions.

EPA agrees. In briefing, it acknowledged that

section 109(b) governs only the “manner” of revisions,

expressly contrasting section 109(b)’s “procedural

requirements” with section 109(d)(1)’s “substantive

authority.” EPA Resp. Br. 34–35. And that is despite

the prior EPA having had every incentive to find

sources of authority when promulgating the Rule and

later defending it. Instead, the prior EPA relied

exclusively on section 109(d)(1). See supra Section

I.B.2; see also Szabo Decl. ¶ 40, Pet. App. 538a.

Any prior revision authority is

constrained by section 109(d)(1).

Regardless, the D.C. Circuit failed to properly

reconcile section 109(b) with section 109(d)(1). Any

revision authority EPA had prior to 1977 must now be

understood in light of section 109(d)(1). Whether that

prior authority was implicit (as petitioners contend)

or conferred by section 109(b) (as the D.C. Circuit

erroneously held),3 section 109(d)(1) added specific

constraints that must be considered. RadLAX

Gateway Hotel, LLC v. Amalgamated Bank, 566 U.S.

639, 645 (2012) (“‘[T]he specific governs the general.’”)

(citation omitted); Varity Corp. v. Howe, 516 U.S. 489,

511 (1996) (“‘the specific governs the general’” canon

is “a warning against applying a general provision

when doing so would undermine limitations created

by a more specific provision”). Indeed, the D.C. Circuit

agreed that it “must read [section 109(b)] in harmony

with [section 109(d)(1)].” Pet. App. 25a.

Doing so properly leads to the conclusion that

section 109(d)(1) imposed new procedural and

3 EPA’s revision authority was implicit in EPA’s power to

promulgate NAAQS. Nat. Res. Def. Council v. Regan, 67 F.4th

397, 401 (D.C. Cir. 2023) (“the power to decide is normally

accompanied by the power to reconsider”).

substantive requirements on all NAAQS revisions, as

explained above. See supra Section I.A. The first

sentence imposes both an action-forcing device

(requiring EPA to review and revise every five years)

and a substantive safeguard (requiring EPA’s review

to be “thorough”). 42 U.S.C. § 7409(d)(1), Pet. App.

468a. The second sentence allows EPA to perform the

same actions, subject to the same substantive

safeguard, “earlier or more frequently than required

under this paragraph.” Ibid.

The D.C. Circuit held instead that section

109(d)(1) did not change anything about off-cycle

NAAQS revisions. But that is not the best reading of

the statute, for the reasons set forth above, supra

Section I.A., and explained further below.

First, the D.C. Circuit misread the text. It failed to

appreciate that the second sentence of section

109(d)(1) simply allows EPA to do “earlier and more

frequently” what is already “required under this

paragraph.” See supra Section I.A. That then led the

court to attribute material meaning to words not

repeated from the first sentence, rather than

acknowledging the second sentence’s use of a

shorthand reference. Ibid. And it further compounded

that error by applying the omitted-case canon to some

of the missing words and not the others. Ibid.

Second, the D.C. Circuit’s reading allows EPA to

end-run the thorough-review requirement, rendering

superfluous a core component of the statutory scheme.

In other words, it allows EPA to do exactly what it did

here—throw out a prior administration’s considered

judgment based on a selective, less-than-thorough offcycle review of the science. That would effectively

nullify the thorough review requirement for on-cycle

revisions and undermine the purpose of requiring a

thorough review at all. See Abramski v. United States,

573 U.S. 169, 179–80 (2014) (rejecting statutory

interpretation that “would virtually repeal [a] … law’s

core provisions”). Given the widespread and

disruptive consequences of a relatively abbreviated

off-cycle revision, supra Statement I.A., it would make

little sense for Congress to “permit,” much less to

encourage, “such gamesmanship.” EPA v. Calumet

Shreveport Refining, L.L.C., 145 S. Ct. 1735, 1748

(2025).

The D.C. Circuit dismissed this concern, reasoning

that any off-cycle revision must still comply with the

“requirement of reasoned decisionmaking,” which

would call for some attention to science. Pet. App. 30a.

But that misses the point. Arbitrary-and-capricious

challenges to NAAQS take years. See, e.g., Mississippi

v. EPA, 744 F.3d 1334 (D.C. Cir. 2013) (per curiam) (5

years); Am. Farm Bureau Fed’n v. EPA, 559 F.3d 512

(D.C. Cir. 2009) (per curiam) (2.5 years); Am.

Trucking Ass’ns, Inc. v. EPA, 283 F.3d 355 (D.C. Cir.

2002) (5 years). And in the meantime, States and

regulated parties bear enormous burdens. See supra

Statement I.A. Even assuming a win in the end—

which is hardly certain given the standard of review—

the delay effectively nullifies the thorough-review

requirement.

Third, the D.C. Circuit repeatedly relied on what

it assumed was the purpose of section 109(d)(1). The

court said “[t]he reason for [the thorough review]

requirement is obvious”: “it serves as an action-forcing

device” by requiring a review-and-revise process every

five years. Pet. App. 23a. In the court’s view, requiring

a “thorough review” for off-cycle revisions would

“undermine … the plain objective of the first sentence”

by preventing EPA “from responding promptly to

changes in the relevant science.” Pet. App. 27a.

That reasoning assumes the conclusion: that the

sole purpose of section 109(d)(1) is to force more

revisions. But “[n]o statute pursues a single policy at

all costs.” Bartenwerfer v. Buckley, 598 U.S. 69, 81

(2023). By its plain text, section 109(d)(1) serves more

than one purpose. It does force EPA to act by

reviewing the criteria and NAAQS every five years.

But it also imposes a substantive safeguard, ensuring

that all standards are based on a “thorough review” of

the relevant science. Congress confirmed as much by

creating, at the same time it added section 109(d)(1),

a “scientific review committee” to advise EPA on

NAAQS. 42 U.S.C. § 7409(d)(2)(A)–(B), Pet. App.

468a–469a; Clean Air Act Amendments of 1977, Pub.

L. No. 95-95, § 106(a), 91 Stat. 685, 691 (1977).

Together, these safeguards aim to ensure that

NAAQS are based on “the latest scientific knowledge.”

42 U.S.C. § 7408(a)(2).

Those two purposes—regular review and sciencebased standards—are perfectly consistent. But even if

they weren’t, the court could not disregard the text in

favor of policy. See Oklahoma v. Castro-Huerta, 597

U.S. 629, 642 (2022) (“[T]he text of a law controls over

purported legislative intentions[.]”); Montgomery v.

Caribe Transp. II, LLC, 146 S. Ct. 1199, 1207 (2026)

(“Better to live with the mystery than rewrite the

statute.”).

Nor does petitioners’ reading contravene the

statute by preventing EPA from responding more

quickly to new information. To begin with, revisions

were not designed to be fast—by statute, the

implementation process alone takes years. See supra

Statement I.A. That said, section 109(d)(1) allows

EPA to act “more often” than five years—it simply

requires a “thorough review” first. And if a source

presents

“an

imminent

and

substantial

endangerment to public health,” EPA can act faster by

utilizing “[e]mergency powers” to “immediately

restrain” that source under 42 U.S.C. § 7603.

Fourth, the D.C. Circuit reasoned that its reading

fit better into the broader statutory context, pointing

to section 108(c)’s allowing EPA to amend criteria

from “‘time to time.’” Pet. App. 29a. But that context

also requires that all criteria “reflect the latest

scientific knowledge,” 42 U.S.C. § 7408(a)(2), and that

all NAAQS must be “based on such criteria,” id.

§ 7409(b)(1), Pet. App. 467a. See supra p.12. The

court’s reading cannot be reconciled with those

definitional provisions.

Finally, petitioners’ reading is supported by both

Skidmore v. Swift & Co., 323 U.S. 134 (1944), and the

major questions doctrine. An agency’s longstanding,

consistent interpretation carries persuasive weight.

Loper Bright Enters., 603 U.S. at 394 (citing

Skidmore). Here, prior to the 2024 Rule, EPA

consistently took the well-reasoned position that

section 109(d) required a thorough review before any

revision. Mot. to Vacate 10–15; Szabo Decl. ¶¶ 36, 38,

Pet. App. 533a–534a, Pet. App. 536a–537a.

The major questions doctrine supports petitioners’

reading for similar reasons. Under that doctrine,

courts are “‘reluctan[t] to read into ambiguous

statutory text’ extraordinary delegations of

Congress’s powers,” particularly where the agency

has never before exercised such authority. Learning

Res., Inc. v. Trump, 607 U.S. 229, 242 (2026) (citations

omitted). Never before has EPA asserted the power to

revise the NAAQS off-cycle without a thorough

review, a regulatory action that has enormous

consequences for the national economy. See supra

Statement II.B. That power is magnified by the CAA’s

anti-backsliding provision, which can limit EPA’s

ability to later relax the NAAQS in nonattainment

areas. See ibid. Whatever else might be said about the

language of section 109, it certainly contains no clear

delegation of that much power, having spawned three

competing interpretations in this case.

II.

The D.C. Circuit wrongly held that EPA

cannot consider costs and attainability in

deciding whether to review and revise a

NAAQS off-cycle.

The D.C. Circuit also erred by holding that EPA is

prohibited from considering costs when deciding

whether to review and revise a NAAQS off-cycle. In

exercising that discretion, EPA must consider costs

and attainability under Michigan v. EPA, 576 U.S.

743 (2015). EPA admits it did not. RTC 120, Pet. App.

483a.

Unless a statute clearly says otherwise, cost is a

“centrally relevant factor” for agencies to consider

“when deciding whether to regulate.” Michigan, 576

U.S. at 753. That is because “reasonable regulation

ordinarily requires paying attention to the

advantages and the disadvantages of agency

decisions.” Ibid. Those “disadvantages” include cost.

See ibid. By extension, they include whether it is

practicable, or even possible, to comply with the

agency’s rule. See All. for Cannabis Therapeutics v.

Drug Enf’t Admin., 930 F.2d 936, 940 (D.C. Cir. 1991)

(it is unreasonable to impose requirements that

regulated parties cannot meet). Agencies must

consider both factors unless Congress “expressly

directs [them] to regulate on the basis of a factor that

on its face does not include cost.” Michigan, 576 U.S.

at 755–56.

At minimum, EPA was required to consider costs

and attainability before deciding to conduct an off-

cycle review. Neither section 109(d)(1) nor section

109(b) expressly prohibits this. As construed in

Whitman, section 109(b) prohibits EPA from

considering costs when deciding what level to set for a

NAAQS during an on-cycle review—since that level

must be “requisite to protect the public health.” But

section 109(b) says nothing about how EPA should

decide the quite different question whether to conduct

a voluntary off-cycle review. Accordingly, EPA’s

failure to consider costs and attainability is an

alternative ground for vacatur, as EPA conceded

below. Mot. to Vacate 18–23.4

The D.C. Circuit erroneously concluded that

Whitman was “controlling.” Pet. App. 33a–34a. There,

this Court addressed the standard for “setting

[NAAQS] under § 109(b)(1), which requires EPA to set

Like its confession of error on the first issue, EPA’s

concession on this issue returned it to the executive branch’s

longstanding understanding. The first time EPA attempted an

off-cycle revision, President Obama and the OIRA Administrator

instructed EPA not to finalize it, citing “regulatory costs and

burdens.” Letter from C. Sunstein, Office of Information and

Regulatory Affairs Administrator, to L. Jackson, EPA

Administrator at 2 (Sept. 2, 2011), https://tinyurl.com/3ykfcy7n

(last visited Aug. 26, 2026); see also Statement by the President

on the Ozone National Ambient Air Quality Standards (Sept. 2,

2011), https://tinyurl.com/ccdte5n7 (citing “regulatory burdens

and regulatory uncertainty” when “withdraw[ing] the draft

Ozone [NAAQS]”). The only other attempted off-cycle revision

EPA abandoned in favor of a thorough review. Press Release,

EPA Initiates New Review of the Ozone National Ambient Air

Quality Standards to Reflect the Latest Science (Aug. 21, 2023),

https://tinyurl.com/mrhc329m (last visited Aug. 26, 2026).

standards “requisite to protect the public health.” 531

U.S. at 462. Whitman held that this language “bars

cost considerations from the NAAQS-setting process.”

Id. at 471.

That holding does not control here. Whitman

addressed how EPA should decide what “level” to set

for a NAAQS during an on-cycle review—not whether

to conduct a discretionary, off-cycle review at all. 531

U.S. at 462. Here, the problem is not just that EPA

ignored costs and attainability when setting a level,

but that EPA also ignored those factors when deciding

whether to initiate the wholly optional off-cycle review

that led to a lower level. Whitman had no occasion to

address that issue, because the agency had

undertaken a mandatory, on-cycle review, not a

discretionary off-cycle review.

The D.C. Circuit acknowledged the difference

between “‘formulating the NAAQS,’” and the “anterior

decision” of whether even to review them. Pet. App.

37a. But the court did “not see how” this difference

“would permit the Administrator to consider costs at

either stage.” Ibid. In other words, the court decreed

both decisions—whether to review and what level to

set—part of the same “NAAQS-setting process” and

claimed that both were governed by Whitman. Pet.

App. 36a.

But these two decisions are different. The costs of

initiating a voluntary off-cycle review include, at

least, the disruption to settled expectations, the

burdens on States and regulated parties, and the risk

that anti-backsliding will lock in a stricter standard

before the next on-cycle review. See supra pp. 11,

Statement I. These are not the costs of setting a level

during an on-cycle review, as EPA now concedes. Mot.

to Vacate 19–20. They stem from EPA’s discretionary

choice to depart from the five-year review cycle that

Congress prescribed. Under Michigan, such

discretionary choices require attention to costs.

By holding otherwise, the D.C. Circuit extended

Whitman’s holding to conflict with Michigan. It also

produced the very irrationality Michigan condemned:

requiring EPA to ignore “billions of dollars in

economic costs” when deciding whether to undertake

a discretionary action it need not pursue. See 576 U.S.

at 752. But if this Court concludes that Whitman

controls in whole or in part, it should reconsider

Whitman’s statutory and constitutional holdings.5

Further, by prohibiting the consideration of costs

and attainability, the D.C. Circuit’s decision raises

serious constitutional issues by reading the CAA to

delegate discretion to decide to undertake a voluntary

and disruptive off-cycle revision without any

threshold guiding principles or constraints. See

Whitman, 531 U.S. at 472 (“Congress must ‘lay down

by legislative act an intelligible principle to which the

5 Cf. Whitman, 531 U.S. at 486-87 (Thomas, J., concurring)

(“express[ing] … concern that there may nevertheless be a

genuine constitutional problem with § 109, a problem which the

parties did not address”).

person or body authorized to act is directed to

conform.’”) (citation omitted).

III.

The

questions

presented

exceptionally important.

are

Revisions

NAAQS

have

enormous

consequences, creating a years-long domino effect that

seriously burdens States and regulated parties. See

supra Statement Section I.A. Implementing the initial

NAAQS takes years, and requires all fifty States to

submit area designations and SIPs—comprehensive

regulatory regimes that are costly to create and

require costly compliance after. Id. Put simply, SIPs

impose “tremendous resource demands” and “huge

administrative burdens.” Env’t Comm. of Fla. Elec.

Power Coordinating Grp., Inc. v. EPA, 94 F.4th 77, 96

(D.C. Cir. 2024) (per curiam).

Revising a NAAQS requires States to redo this

entire process, while also instantly tightening

permitting requirements and subjecting prior

nonattainment areas to the strictest standards

nationwide. Supra Statement I.A. As noted, the

immediate effect on pre-construction permitting

applies both to new and pending applications. And for

nonattainment areas, any new or modified sources

must “comply with the lowest achievable emission

rate.” 42 U.S.C. § 7503(a)(2). As also explained above,

that means the most stringent emissions limit in any

State’s SIP or achieved in practice. Revisions thus

severely disrupt long-term infrastructure and

industrial projects. Supra Statement I.A.

When EPA revises a NAAQS off-cycle, disruption

is greater still, as States and regulated parties may

still be implementing the last standard when they are

forced to implement an even stricter standard. Ibid.

Off-cycle revisions thus upend reliance interests

across the regulatory system. States may still be

developing SIPs for the prior standard when a further

revision requires them to pivot—reevaluating area

designations, revising emissions limits and control

strategies, and redirecting resources to a new round

of implementation. Major industrial projects,

infrastructure investments, and long-term capital

planning all depend on regulatory stability. An offcycle revision can render years of planning and

expenditure obsolete.

The questions presented concern two important

safeguards on these off-cycle revisions. First,

Congress required a thorough review for all revisions

(on-cycle or off) precisely because of these immense

consequences. If EPA wants to impose those

consequences, it must rely on a thorough review of the

latest science. Second, EPA must at least consider

costs and attainability when launching a

discretionary off-cycle review. The D.C. Circuit’s

decision eliminates both protections: allowing EPA to

upend regulatory regimes in all fifty States without

fully understanding the science or considering costs

and other consequences of an entirely voluntary

action.

This Court has rigorously enforced similar

safeguards on agency decision-making. The

requirements to provide a rational explanation, Motor

Vehicle Mfrs. Ass’n v. State Farm Mut. Auto. Ins. Co.,

463 U.S. 29, 43 (1983), to acknowledge a change in

position, Encino Motorcars, LLC v. Navarro, 579 U.S.

211, 221 (2016), and to address reliance

interests, Regents, 591 U.S. at 30–33, all similarly

ensure that the agency at least confronts, rather than

ignores, important questions. The thorough-review

requirement and the obligation to consider costs serve

that same structural function.

Finally, both questions are even more important

because EPA cannot readily correct errors through

further rulemaking. The CAA’s anti-backsliding

provision may effectively prevent EPA from relaxing

an ill-considered standard—even if a subsequent,

thorough review concludes that EPA should do so. See

supra p. 11; 42 U.S.C. § 7502(e). That feature of the

statutory scheme makes it all the more important for

this Court to require EPA to comply with the statute,

and avoid unlawful shortcuts, when it decides to

revise a standard.

CONCLUSION

The petition for a writ of certiorari should be

granted, as should the separate petition from the

same judgment filed by the petitioner States.

August 28, 2026

Respectfully submitted,

LUCINDA MINTON

LANGWORTHY

ERICA N. PETERSON

HUNTON ANDREWS

KURTH LLP

2200 Pennsylvania

Avenue, NW, Suite 900

Washington, D.C. 20037

(202) 955-1500

ELBERT LIN

Counsel of Record

DAVID M. PARKER

HUNTON ANDREWS

KURTH LLP

951 East Byrd Street,

East Tower

Richmond, VA 23219

elin@Hunton.com

(804) 788-8200

Counsel for Petitioners Chamber of Commerce of the

United States of America, American Cement

Association, American Chemistry Council, American

Forest & Paper Association, American Petroleum

Institute, American Wood Council, National

Association of Manufacturers, and National Mining

Association

MATTHEW Z. LEOPOLD

HOLLAND & KNIGHT

800 17TH STREET,

N.W.,

SUITE 1100

WASHINGTON, D.C.

20006

Counsel for Petitioners

Chamber of Commerce

of the United States of

America, American

Cement Association,

American Chemistry

Council, American

Forest & Paper

Association, American

Petroleum Institute,

American Wood

Council, National

Association of

Manufacturers, and

National Mining

Association

DARYL JOSEFFER

ANDREW R. VARCOE

STEPHANIE A.

MALONEY

U.S. CHAMBER

LITIGATION CENTER

1615 H STREET, NW

WASHINGTON, D.C.

20062

Counsel for Petitioner

Chamber of Commerce

of the United States of

America

LEAH PILCONIS

CHRISTINE MCCARTHY

AMERICAN CEMENT

ASSOCIATION

200 MASSACHUSETTS

AVE NW, SUITE 200

WASHINGTON, D.C.

20001

Counsel for Petitioner

American Cement

Association

ELLIOTT ZENICK

AMERICAN CHEMISTRY

COUNCIL

655 NEW YORK AVE.

WASHINGTON DC 20001

Counsel for Petitioner

American Chemistry

Council

ERICA KLENICKI

CAROLINE T.

MCAULIFFE

NAM LEGAL CENTER

733 TENTH STREET,

SUITE 700

WASHINGTON, D.C.

20001

Counsel for Petitioner

National Association of

Manufacturers

TAWNY BRIDGEFORD

NATIONAL MINING

ASSOCIATION

101 CONSTITUTION

AVE., NW, SUITE 500

EAST

WASHINGTON, D.C.

20001

Counsel for Petitioner

National Mining

Association

EMILY C. SCHILLING

SYDNEY J. SELL

HOLLAND & HART LLP

222 SOUTH MAIN

STREET, SUITE 2200

SALT LAKE CITY, UT

84101

KRISTINA (TINA) R. VAN

BOCKERN

HOLLAND & HART LLP

555 SEVENTEENTH

STREET, SUITE 3200

DENVER, CO 80202

Counsel for Petitioner

Essential Minerals

Association

BRUNN (BEAU) W.

ROYSDEN III

CULPER LAW PLLC

111 W. MARSHALL AVE.

PHOENIX, AZ 85013

Counsel for Petitioners

Warren Petersen,

President of the

Arizona State Senate,

and Steve Montenegro,

Speaker of the Arizona

House of

Representatives

VANESSA M. POMEROY

ARIZONA CHAMBER OF

COMMERCE &

INDUSTRY

100 N. 7TH AVENUE,

#120

PHOENIX, AZ 85007ௗ

Counsel for Petitioner

Arizona Chamber of

Commerce & Industry

This is a copy of a public record, reproduced as it was published. It is not legal advice, and it may not be the version a court would rely on. Check the official source before you cite it.