No. 

In the Supreme Court of the United States 

CAROL M. BROWNER, ADMINISTRATOR OF THE 

ENVIRONMENTAL PROTECTION AGENCY, ET AL., 
PETITIONERS 

v. 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL. 

ON PETITION FOR A WRIT OF CERTIORARI 
TO THE UNITED STATES COURT OF APPEALS 
FOR THE DISTRICT OF COLUMBIA CIRCUIT 

APPENDIX TO THE 
PETITION FOR A WRIT OF CERTIORARI 

GARY S. GUZY 

General Counsel 

ROBERT G. DREHER 

Deputy General Counsel 

GERALD K. GLEASON 
MICHAEL L. GOO 
AMEY W. MARRELLA 
JAN M. TIERNEY 
KEVIN W. MCLEAN 

Attorneys 
Environmental Protection 

Agency 
Washington, D.C. 20460 
SETH P. WAXMAN 

Solicitor General 

Counsel of Record 

LOIS J. SCHIFFER 

Assistant Attorney General 

LAWRENCE G. WALLACE 

Deputy Solicitor General 

JEFFREY P. MINEAR 

Assistant to the Solicitor 

General 

DAVID J. KAPLAN 
MARY F. EDGAR 

Attorneys 

Department of Justice 
Washington, D.C. 20530-0001 
(202) 514–2217 

TABLE OF CONTENTS 

Page 

Appendix A (court of appeals’ opinion, dated May 14, 
1999) ................................................................................ 1a 

Appendix B: 
(court of appeals’ opinion on rehearing, dated 

October 29, 1999) ..................................................... 
70a 

(court of appeals’ dissenting statements on re- 
hearing en banc, dated October 29, 1999) ............ 
90a 

Appendix C (regulatory provisions, 40 C.F.R. 

50.7) ........................................................................... 102a 

Appendix D (regulatory provisions, 40 C.F.R. 

50.10) ......................................................................... 104a 

Appendix E (statutory provisions, 42 U.S.C. 7407, 
7408, 7409, 7502, 7511, 7607) ...................................... 105a 

(I) 

APPENDIX A 

UNITED STATES COURT OF APPEALS 
FOR THE DISTRICT OF COLUMBIA CIRCUIT 

No. 97-1440 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

Consolidated with 
Nos. 97-1546, 97-1548, 97-1551, 97-1552, 97-1553, 
97-1555, 97-1559, 97-1561, 97-1562, 97-1565, 97-1567, 
97-1571, 97-1573, 97-1574, 97-1576, 97-1578, 97-1579, 
97-1582, 97-1585, 97-1586, 97-1587, 97-1588, 97-1592, 
97-1594, 97-1596, 97-1597, 97-1598 

(1a) 

2a 

97-1441 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

Consolidated with 
Nos. 97-1502, 97-1505, 97-1508, 97-1509, 97-1510, 
97-1512, 97-1513, 97-1514, 97-1518, 97-1519, 97-1526, 
97-1531, 97-1539, 97-1566, 97-1568, 97-1570, 97-1572, 
97-1575, 97-1584, 97-1589, 97-1591, 97-1595, 97-1619 

[Decided May 14, 1999] 
[Argued December 17, 1998] 

3a 

On Petitions for Review of an Order of the 

Environmental Protection Agency 

BEFORE: WILLIAMS, GINSBURG and TATEL, Circuit 

Judges. 

Opinion for the Court filed PER CURIAM.* 

Separate opinion dissenting from Part I filed by 
Circuit Judge Tatel. 

PER CURIAM: 

Introduction 

The Clean Air Act requires EPA to promulgate and 
periodically revise national ambient air quality stan- 
dards (“NAAQS”) for each air pollutant identified by 
the agency as meeting certain statutory criteria. See 
Clean Air Act §§ 108-09, 42 U.S.C. §§ 7408-09. For each 
pollutant, EPA sets a “primary standard”—a concen- 
tration level “requisite to protect the public health” 
with an “adequate margin of safety”—and a “secondary 
standard”—a level “requisite to protect the public 
welfare.” Id. § 7409(b). 

In July 1997 EPA issued final rules revising the pri- 
mary and secondary NAAQS for particulate matter 
(“PM”) and ozone. See National Ambient Air Quality 
Standards for Particulate Matter, 62 Fed. Reg. 38,652 
(1997) (“PM Final Rule”); National Ambient Air Quality 
Standards for Ozone, 62 Fed. Reg. 38,856 (1997) 
(“Ozone Final Rule”). Numerous petitions for review 
have been filed for each rule. 

* Judge Williams wrote Parts I and III.B; Judge Ginsburg 
wrote Parts II, III.A, and IV.D; Judge Tatel wrote Parts IV.A-C. 

4a 

In Part I we find that the construction of the Clean 
Air Act on which EPA relied in promulgating the 
NAAQS at issue here effects an unconstitutional 
delegation of legislative power. See U.S. Const. art. I, 
§ 1 (“All legislative powers herein granted shall be 
vested in a Congress of the United States.”). We 
remand the cases for EPA to develop a construction of 
the act that satisfies this constitutional requirement. 

In Part II we reject the following claims: that 
§ 109(d) of the Act allows EPA to consider costs; that 
EPA should have considered the environmental dam- 
age likely to result from the NAAQS’ financial impact 
on the Abandoned Mine Reclamation Fund; that the 
NAAQS revisions violated the National Environmental 
Policy Act (“NEPA”), Unfunded Mandates Reform Act 
(“UMRA”), and Regulatory Flexibility Act (“RFA”). 

In Part III we decide two ozone-specific statutory 
issues, holding that the 1990 revisions to the Clean Air 
Act limit EPA’s ability to enforce new ozone NAAQS 
and that EPA cannot ignore the possible health bene- 
fits of ozone. 

Finally, in Part IV we resolve various challenges to 
the PM NAAQS. We agree with petitioners that 
EPA’s choice of PM10 as the indicator for coarse particu- 
late matter was arbitrary and capricious; we reject 
petitioners’ claims that EPA must treat PM2.5 as a “new 
pollutant,” that EPA must identify a biological mecha- 
nism explaining PM’s harmful effects, and that the 
Clean Air Act requires secondary NAAQS to be set at 
levels that eliminate all adverse visibility effects. 

5a 

The remaining issues cannot be resolved until such 
time as EPA may develop a constitutional construction 
of the act (and, if appropriate, modify the disputed 
NAAQS in accordance with that construction). 

I. Delegation 

Certain “Small Business Petitioners” argue in each 
case that EPA has construed §§ 108 & 109 of the Clean 
Air Act so loosely as to render them unconstitutional 
delegations of legislative power. We agree. Although 
the factors EPA uses in determining the degree of 
public health concern associated with different levels of 
ozone and PM are reasonable, EPA appears to have 
articulated no “intelligible principle” to channel its 
application of these factors; nor is one apparent from 
the statute. The nondelegation doctrine requires such a 
principle. See J.W. Hampton, Jr. & Co. v. United 
States, 276 U.S. 394, 409 (1928). Here it is as though 
Congress commanded EPA to select “big guys,” and 
EPA announced that it would evaluate candidates 
based on height and weight, but revealed no cut-off 
point. The announcement, though sensible in what it 
does say, is fatally incomplete. The reasonable person 
responds, “How tall? How heavy?” 

EPA regards ozone definitely, and PM likely, as non- 
threshold pollutants, i.e., ones that have some possibil- 
ity of some adverse health impact (however slight) at 
any exposure level above zero. See Ozone Final Rule, 
62 Fed. Reg. at 38,863/3 (“Nor does it seem possible, in 
the Administrator’s judgment, to identify [an ozone 
concentration] level at which it can be concluded with 
confidence that no ‘adverse’ effects are likely to 
occur.”); National Ambient Air Quality Standards for 
Ozone and Particulate Matter, 61 Fed. Reg. 65,637, 

6a 

65,651/3 (1996) (proposed rule) (“[T]he single most 
important factor influencing the uncertainty associated 
with the risk estimates is whether or not a threshold 
concentration exists below which PM-associated health 
risks are not likely to occur.”). For convenience, we 
refer to both as non-threshold pollutants; the indetermi- 
nacy of PM’s status does not affect EPA’s analysis, or 
ours. 

Thus the only concentration for ozone and PM that is 
utterly risk-free, in the sense of direct health impacts, 
is zero. Section 109(b)(1) says that EPA must set each 
standard at the level “requisite to protect the public 
health” with an “adequate margin of safety.” 42 U.S.C. 
§ 7409(b)(1). These are also the criteria by which EPA 
must determine whether a revision to existing NAAQS 
is appropriate. See 42 U.S.C. § 7409(d)(1) (EPA shall 
“promulgate such new standards as may be appropriate 
in accordance with . . . [§ 7409(b)]”); see also infra 
Part II.A. For EPA to pick any non-zero level it must 
explain the degree of imperfection permitted. The 
factors that EPA has elected to examine for this 
purpose in themselves pose no inherent nondelegation 
problem. But what EPA lacks is any determinate crite- 
rion for drawing lines. It has failed to state intelligibly 
how much is too much. 

We begin with the criteria EPA has announced for 
assessing health effects in setting the NAAQS for non- 
threshold pollutants.1 They are “the nature and sever- 

1 Technically, EPA describes the criteria as used only for 
setting the “adequate margin of safety.” There might be thought 
to be a separate step in which EPA determines what standard 
would protect public health without any margin of safety, and that 
step might be governed by different criteria. But EPA did not use 

7a 

ity of the health effects involved, the size of the sensi- 
tive population(s) at risk, the types of health informa- 
tion available, and the kind and degree of uncertainties 
that must be addressed.” Ozone Final Rule, 62 Fed. 
Reg. at 38,883/2; EPA, “Review of the National Ambi- 
ent Air Quality Standards for Particulate Matter: 
Policy Assessment of Scientific and Technical Informa- 
tion: OAQPS Staff Paper,” at II-2 (July 1996) (“PM 
Staff Paper”) (listing same factors). Although these 
criteria, so stated, are a bit vague, they do focus the 
inquiry on pollution’s effects on public health. And most 
of the vagueness in the abstract formulation melts away 
as EPA applies the criteria: EPA basically considers 
severity of effect, certainty of effect, and size of popula- 
tion affected. These criteria, long ago approved by the 
judiciary, see Lead Industries Ass’n v. EPA, 647 F.2d 
1130, 1161 (D.C. Cir. 1980) (“Lead Industries”), do not 
themselves speak to the issue of degree. 

Read in light of these factors, EPA’s explanations for 
its decisions amount to assertions that a less stringent 
standard would allow the relevant pollutant to inflict a 
greater quantum of harm on public health, and that a 
more stringent standard would result in less harm. 
Such arguments only support the intuitive proposition 
that more pollution will not benefit public health, not 
that keeping pollution at or below any particular level is 
“requisite” or not requisite to “protect the public 
health” with an “adequate margin of safety,” the for- 
mula set out by § 109(b)(1). 

such a process, and it need not. See NRDC v. EPA, 902 F.2d 963, 
973 (D.C. Cir. 1990). Thus, the criteria mentioned in the text gov- 
ern the whole standard-setting process. 

8a 

Consider EPA’s defense of the 0.08 ppm level of the 
ozone NAAQS. EPA explains that its choice is superior 
to retaining the existing level, 0.09 ppm, because more 
people are exposed to more serious effects at 0.09 than 
at 0.08. See Ozone Final Rule, 62 Fed. Reg. at 38,868/1. 
In defending the decision not to go down to 0.07, EPA 
never contradicts the intuitive proposition, confirmed 
by data in its Staff Paper, that reducing the standard to 
that level would bring about comparable changes. See 
EPA, “Review of National Ambient Air Quality Stan- 
dards for Ozone: Assessment of Scientific and Technical 
Information: OAQPS Staff Paper,” at 156 (June 1996) 
(“Ozone Staff Paper”). Instead, it gives three other 
reasons. The principal substantive one is based on the 
criteria just discussed: 

The most certain O3-related effects, while judged to 
be adverse, are transient and reversible (particu- 
larly at O3 exposures below 0.08 ppm), and the more 
serious effects with greater immediate and potential 
long-term impacts on health are less certain, both as 
to the percentage of individuals exposed to various 
concentrations who are likely to experience such 
effects and as to the long-term medical significance 
of these effects. 

Ozone Final Rule, 62 Fed. Reg. at 38,868/2. 

In other words, effects are less certain and less 
severe at lower levels of exposure. This seems to be 
nothing more than a statement that lower exposure 
levels are associated with lower risk to public health. 
The dissent argues that in setting the standard at 0.08, 
EPA relied on evidence that health effects occurring 
below that level are “transient and reversible,” Dissent 
at 5, evidently assuming that those at higher levels are 

9a 

not. But the EPA language quoted above does not 
make the categorical distinction the dissent says it 
does, and it is far from apparent that any health effects 
existing above the level are permanent or irreversible. 

In addition to the assertion quoted above, EPA cited 
the consensus of the Clean Air Scientific Advisory 
Committee (“CASAC”) that the standard should not be 
set below 0.08. That body gave no specific reasons for 
its recommendations, so the appeal to its authority, also 
made in defense of other standards in the PM Final 
Rule, see PM Final Rule, 62 Fed. Reg. at 38,677/2 (daily 
fine PM standard); id. at 38,678/3 (annual coarse PM 
standard); id. at 38,679/1 (daily coarse PM standard), 
adds no enlightenment. The dissent stresses the undis- 
puted eminence of CASAC’s members, Dissent at 4, but 
the question whether EPA acted pursuant to lawfully 
delegated authority is not a scientific one. Nothing in 
what CASAC says helps us discern an intelligible 
principle derived by EPA from the Clean Air Act. 

Finally, EPA argued that a 0.07 standard would be 
“closer to peak background levels that infrequently 
occur in some areas due to nonanthropogenic sources of 
O3 precursors, and thus more likely to be inappropri- 
ately targeted in some areas on such sources.” Ozone 
Final Rule, 62 Fed. Reg. at 38,868/3. But a 0.08 level, of 
course, is also closer to these peak levels than 0.09. The 
dissent notes that a single background observation fell 
between 0.07 and 0.08, and says that EPA’s decision 
“ensured that if a region surpasses the ozone standard, 
it will do so because of controllable human activity, not 
uncontrollable natural levels of ozone.” Dissent at 6. 
EPA’s language, coupled with the data on background 
ozone levels, may add up to a backhanded way of saying 

10a 

that, given the national character of the NAAQS, it is 
inappropriate to set a standard below a level that can 
be achieved throughout the country without action 
affirmatively extracting chemicals from nature. That 
may well be a sound reading of the statute, but EPA 
has not explicitly adopted it. 

EPA frequently defends a decision not to set a 
standard at a lower level on the basis that there is 
greater uncertainty that health effects exist at lower 
levels than the level of the standard. See Ozone Final 
Rule, 62 Fed. Reg. at 38,868/2; PM Final Rule, 62 Fed. 
Reg. at 38,676/3 (annual fine PM standard); id. at 
38,677/2 (daily fine PM standard). And such an argu- 
ment is likely implicit in its defense of the coarse PM 
standards. See PM Final Rule, 62 Fed. Reg. at 
38,678/3-79/1. The dissent’s defense of the fine particu- 
late matter standard cites exactly such a justification. 
See Dissent at 6 (“The Agency explained that ‘there is 
generally greatest statistical confidence in observed 
associations . . . for levels at and above the mean con- 
centration [in certain studies]’ ”) (emphasis added in 
dissent). But the increasing-uncertainty argument is 
helpful only if some principle reveals how much uncer- 
tainty is too much. None does. 

The arguments EPA offers here show only that EPA 
is applying the stated factors and that larger public 
health harms (including increased probability of such 
harms) are, as expected, associated with higher pollut- 
ant concentrations. The principle EPA invokes for each 
increment in stringency (such as for adopting the 
annual coarse particulate matter standard that it chose 
here)—that it is “possible, but not certain” that health 
effects exist at that level, see PM Final Rule, 62 Fed. 

11a 

Reg. at 38,678/32—could as easily, for any non-threshold 
pollutant, justify a standard of zero. The same 
indeterminacy prevails in EPA’s decisions not to pick a 
still more stringent level. For example, EPA’s reasons 
for not lowering the ozone standard from 0.08 to 0.07 
ppm—that “the more serious effects . . . are less cer- 
tain” at the lower levels and that the lower levels are 
“closer to peak background levels,” see Ozone Final 
Rule, 62 Fed. Reg. at 38,868/2—could also be employed 
to justify a refusal to reduce levels below those associ- 
ated with London’s “Killer Fog” of 1952. In that 
calamity, very high PM levels (up to 2,500 •g/m3) are 
believed to have led to 4,000 excess deaths in a week.3 
Thus, the agency rightly recognizes that the question is 
one of degree, but offers no intelligible principle by 
which to identify a stopping point. 

The latitude EPA claims here seems even broader 
than that OSHA asserted in International Union, 
UAW v. OSHA (“Lockout/Tagout I”), 938 F.2d 1310, 
1317 (D.C. Cir. 1991), which was to set a standard that 
would reduce a substantial risk and that was not 
infeasible. In that case, OSHA thought itself free 
either to “do nothing at all” or to “require precautions 
that take the industry to the brink of ruin,” with “all 

2 EPA did cite qualitative evidence for further support for its 
annual standard, and argued that the evidence “does not provide 
evidence of effects below the range of 40-50 •g/m3,” the standard 
level. PM Final Rule, 62 Fed. Reg. at 38,678/3. The referenced 
document, however, bears no indication that the qualitative evi- 
dence demonstrates effects at the level of the standard, either. 
See EPA, “Air Quality Criteria for Particulate Matter,” at 13-79 
(April 1996). 

3 See W.P.D. Logan, “Mortality in the London Fog Incident, 
1952,” The Lancet, Feb. 4, 1953, at 336-38. 

12a 

positions in between . . . evidently equally valid.” Id. 
Here, EPA’s freedom of movement between the poles 
is equally unconstrained, but the poles are even farther 
apart—the maximum stringency would send industry 
not just to the brink of ruin but hurtling over it, while 
the minimum stringency may be close to doing nothing 
at all. 

In Lockout/Tagout I certain special conditions that 
have justified an exceptionally relaxed application of 
the nondelegation doctrine were absent, id. at 1317-18, 
and they are equally absent here. The standards in 
question affect the whole economy, requiring a “more 
precise” delegation than would otherwise be the case, 
see A.L.A. Schechter Poultry Corp. v. United States, 
295 U.S. 495, 553 (1935). No “special theories” justify- 
ing vague delegation such as the war powers of the 
President or the sovereign attributes of the delegatee 
have been or could be asserted. Nor is there some 
inherent characteristic of the field that bars develop- 
ment of a far more determinate basis for decision. (This 
is not to deny that there are difficulties; we consider 
some below.) 

EPA cites prior decisions of this Court holding that 
when there is uncertainty about the health effects of 
concentrations of a particular pollutant within a par- 
ticular range, EPA may use its discretion to make the 
“policy judgment” to set the standards at one point 
within the relevant range rather than another. NRDC 

v. EPA, 902 F.2d 962, 969 (D.C. Cir. 1990); American 
Petroleum Inst. v. Costle, 665 F.2d 1176, 1185 (D.C. Cir. 
1981); Lead Industries, 647 F.2d at 1161 (D.C. Cir. 
1980). We agree. But none of those panels addressed 
the claim of undue delegation that we face here, and 

13a 

accordingly had no occasion to ask EPA for coherence 
(for a “principle,” to use the classic term) in making its 
“policy judgment.” The latter phrase is not, after all, a 
self-sufficient justification for every refusal to define 
limits. 

It was suggested at oral argument that EPA’s vision 
of its discretion in application of § 109(b)(1) is no 
broader than that asserted by OSHA after a remand by 
this court and upheld by this court in International 
Union, UAW v. OSHA (“Lock-out/Tagout II”), 37 F.3d 
665 (D.C. Cir. 1994). But there, in fact, OSHA allowed 
itself to set only standards falling somewhere between 
maximum feasible stringency and some “moderate” 
departure from that level. Id. at 669. As our prior dis- 
cussion should have indicated, here EPA’s formulation 
of its policy judgment leaves it free to pick any point 
between zero and a hair below the concentrations 
yielding London’s Killer Fog. 

The dissent argues that a nondelegation challenge 
similar to this one was rejected in South Terminal 
Corp. v. EPA, 504 F.2d 646 (1st Cir. 1974), and cites 
that case’s language that “the rationality of the means 
can be tested against goals capable of fairly precise 
definition in the language of science,” id. at 677. See 
Dissent at 2. But the action challenged in South Termi- 
nal was EPA’s adoption of a plan for ending or pre- 
venting violations in Boston of already-established 
NAAQS, not its promulgation of the NAAQS them- 
selves. Thus, it seems likely that the “means” were the 
plan’s provisions—e.g., a prohibition on most new park- 
ing in the city, see 504 F.2d at 671, and the “fairly pre- 
cise[ly] defin[ed]” goals were the NAAQS themselves. 

14a 

Where (as here) statutory language and an existing 
agency interpretation involve an unconstitutional dele- 
gation of power, but an interpretation without the 
constitutional weakness is or may be available, our 
response is not to strike down the statute but to give 
the agency an opportunity to extract a determinate 
standard on its own. Lockout/Tagout I, 938 F.2d at 
1313. Doing so serves at least two of three basic 
rationales for the nondelegation doctrine. If the agency 
develops determinate, binding standards for itself, it is 
less likely to exercise the delegated authority arbitrar- 
ily. See Amalgamated Meat Cutters v. Connally, 337 
F. Supp. 737, 758-59 (D.D.C. 1971) (Leventhal, J., for 
three-judge panel). And such standards enhance the 
likelihood that meaningful judicial review will prove 
feasible. See id. at 759. A remand of this sort of course 
does not serve the third key function of non-delegation 
doctrine, to “ensure[ ] to the extent consistent with 
orderly governmental administration that important 
choices of social policy are made by Congress, the 
branch of our Government most responsive to the popu- 
lar will,” Industrial Union Dep’t, AFL-CIO v. Ameri- 
can Petroleum Inst., 448 U.S. 607, 685 (1980) (“Ben- 
zene”) (Rehnquist, J., concurring). The agency will 
make the fundamental policy choices. But the remand 
does ensure that the courts not hold unconstitutional a 
statute that an agency, with the application of its 
special expertise, could salvage. In any event, we do 
not read current Supreme Court cases as applying the 
strong form of the nondelegation doctrine voiced in 
Justice Rehnquist’s concurrence. See Mistretta v. 
United States, 488 U.S. 361, 377-79 (1989). 

What sorts of “intelligible principles” might EPA 
adopt? Cost-benefit analysis, mentioned as a possibility 

15a 

in Lock-out/Tagout I, 938 F.2d at 1319-21, is not avail- 
able under decisions of this court. Our cases read 
§ 109(b)(1) as barring EPA from considering any factor 
other than “health effects relating to pollutants in the 
air.” NRDC, 902 F.2d at 973; see also Lead Industries, 
647 F.2d at 1148; American Lung Ass’n v. EPA, 134 
F.3d 388, 389 (D.C. Cir. 1998); American Petroleum 
Inst., 665 F.2d at 1185 (echoing the same themes). 

In theory, EPA could make its criterion the eradica- 
tion of any hint of direct health risk. This approach is 
certainly determinate enough, but it appears that it 
would require the agency to set the permissible levels 
of both pollutants here at zero. No party here appears 
to advocate this solution, and EPA appears to show no 
inclination to adopt it.4 

EPA’s past behavior suggests some readiness to 
adopt standards that leave non-zero residual risk. For 
example, it has employed commonly used clinical crite- 
ria to determine what qualifies as an adverse health 

4 A zero-risk policy might seem to imply de-industrialization, 
but in fact even that seems inadequate to the task (and even if the 
calculus is confined to direct risks from pollutants, as opposed to 
risks from the concomitant poverty). First, PM (at least) results 
from almost all combustion, so only total prohibition of fire or uni- 
versal application of some heretofore unknown control technology 
would reduce manmade emissions to zero. See PM Staff Paper at 
IV-1. Second, the combustion associated with pastoral life appears 
to be rather deadly. See World Bank, World Development Report 
1992: Development and the Environment 52 (1992) (noting that 
“biomass” fuels (i.e., wood, straw, or dung) are often the only fuels 
that “poor households, mostly in rural areas” can obtain or afford, 
and that indoor smoke from biomass burning “contributes to acute 
respiratory infections that cause an estimated 4 million deaths 
annually among infants and children.”). 

16a 

effect. See Ozone Staff Paper at 59-60 (using American 
Thoracic Society standards to determine threshold for 
“adverse health effect” from ozone). On the issue of 
likelihood, for some purposes it might be appropriate to 
use standards drawn from other areas of the law, such 
as the familiar “more probable than not” criterion. 

Of course a one-size-fits-all criterion of probability 
would make little sense. There is no reason why the 
same probability should govern assessments of a risk of 
thousands of deaths as against risks of a handful of 
people suffering momentary shortness of breath. More 
generally, all the relevant variables seem to range 
continuously from high to low: the possible effects of 
pollutants vary from death to trivialities, and the size of 
the affected population, the probability of an effect, and 
the associated uncertainty range from “large” numbers 
of persons with point estimates of high probability, to 
small numbers and vague ranges of probability. This 
does not seem insurmountable. Everyday life compels 
us all to make decisions balancing remote but severe 
harms against a probability distribution of benefits; 
people decide whether to proceed with an operation 
that carries a 1/1000 possibility of death, and (simplify- 
ing) a 90% chance of cure and a 10% chance of no effect, 
and a certainty of some short-term pain and nuisance. 
To be sure, all that requires is a go/no-go decision, while 
a serious effort at coherence under § 109(b)(1) would 
need to be more comprehensive. For example, a range 
of ailments short of death might need to be assigned 
weights. Nonetheless, an agency wielding the power 
over American life possessed by EPA should be capable 
of developing the rough equivalent of a generic unit of 
harm that takes into account population affected, sever- 
ity and probability. Possible building blocks for such a 

17a 

principled structure might be found in the approach 
Oregon used in devising its health plan for the poor. In 
determining what conditions would be eligible for 
treatment under its version of Medicaid, Oregon ranked 
treatments by the amount of improvement in “Quality- 
Adjusted Life Years” provided by each treatment, di- 
vided by the cost of the treatment.5 Here, of course, 

5 The “quality” of various health states was determined by poll, 
and medical professionals determined the probabilities and dura- 
tions of various health states with and without the treatment in 

question. 

Oregon was twice forced to revise its system because the 
United States Department of Health & Human Services dete- 
mined that the original proposal and a revision violated the Ameri- 
cans with Disabilities Act, 42 U.S.C. §§ 12101-12213. The reason 
given for this determination was that both versions undervalued 
the lives of persons with disabilities: The original plan measured 
quality of life according to the attitudes of the general population 
rather than the attitudes of persons with disabilities. See HHS, 
“Analysis Under the Americans with Disabilities Act (‘ADA’) of 
the Oregon Reform Demonstration” (Aug. 3, 1992), reprinted in 9 
Issues in L. & Med. 397, 410, 410 (1994). The revised plan ranked 
treatments leaving the patient in a “symptomatic” state lower than 
those leaving the patient asymptomatic, and certain disabling con- 
ditions were considered “symptoms.” See Letter from Timothy B. 
Flanagan, Assistant Attorney General, to Susan K. Zagame, Act- 
ing General Counsel, HHS (Jan. 19, 1993), reprinted in 9 Issues in 
L. & Med. 397, 418, 421 (1994). The Department’s determination 
was extensively criticized when issued. See Maxwell J. Mehlman et 
al., “When Do Health Care Decisions Discriminate Against Per- 
sons with Disabilities?” 22 J. Of Health Politics, Policy & L. 1385, 
1390 (1997) (HHS’s “decision provoked a storm of disbelief and 
denunciation”). 

We take no position on whether HHS’s view was correct, or 
if the underlying norm also governs EPA’s decisions under 
§ 109(b)(1). An affirmative answer, however, would not seem to 
preclude use of some of Oregon’s approach. The first step would 
be giving appropriate weight to the views of persons with 

18a 

EPA may not consider cost, and indeed may well find a 
completely different method for securing reasonable 
coherence. Alternatively, if EPA concludes that there 
is no principle available, it can so report to the Con- 
gress, along with such rationales as it has for the levels 
it chose, and seek legislation ratifying its choice. 

We have discussed only the primary standards. Be- 
cause the secondary standards are at least in part based 
on those, see Ozone Final Rule, 62 Fed. Reg. at 
38,875/3-76/1; PM Final Rule, 62 Fed. Reg. at 38,680/3, 
we also remand the cases to the agency with regard to 
the secondary standards as well, for further considera- 
tion in light of this opinion. 

II. Other General Claims 

The petitioners and amici contend that the EPA erro- 
neously failed to consider a host of factors in revising 
the PM and ozone NAAQS. We reject each of these 
claims in turn. 

disabilities. The second might be measuring the seriousness of a 
pollution-induced health effect by the absolute level of well-being 
that the effect brings about, not by the decrease in level that the 
effect causes. In other words, if the maximum well-being level is 
100 and the average asthmatic whose asthma constitutes a dis- 
ability has a well-being of 80 in the absence of air pollution (accord- 
ing to a measure that appropriately considers asthmatics’ own 
assessments of their condition), then a response to air pollution 
that reduces the asthmatics’ well-being to 70 could be counted as 
an effect of magnitude 30 (the difference from full health), rather 
than 10 (the difference from the level without the pollution). That 
approach would ensure that effects on persons with disabilities 
were not underestimated, even in the broad sense of that term 
apparently adopted by HHS. 

19a 

A. Consideration of Cost in Revising Standards 

As this court long ago made clear, in setting NAAQS 
under § 109(b) of the Clean Air Act, the EPA is not per- 
mitted to consider the cost of implementing those 
standards. See Lead Industries, 647 F.2d at 1148 (D.C. 
Cir. 1980); see also NRDC, 902 F.2d at 973 (following 
Lead Industries in reviewing particulate matter 
NAAQS); American Petroleum Inst., 665 F.2d at 1185 
(same, in reviewing ozone NAAQS). The petitioners 
make four unsuccessful attempts to distinguish Lead 
Industries and its progeny. 

First, the petitioners claim that in Lead Industries 
we held only that the Clean Air Act does not compel the 
EPA to consider the costs of implementation in setting 
a NAAQS; on the contrary, we held that the Act 
precludes the EPA from doing so. See Lead Industries, 
647 F.2d at 1148 (“the statute and its legislative history 
make clear that economic considerations play no part in 
the promulgation of [NAAQS]”). 

Second, that we decided Lead Industries prior to the 
Supreme Court’s decision in Chevron U.S.A. Inc. v. 
NRDC, 467 U.S. 837 (1984) does not, as the petitioners 
suggest, require us to revisit the earlier case. The Lead 
Industries decision was made in Chevron step one 
terms, see id., as the post-Chevron progeny of Lead 
Industries have made clear. See NRDC, 902 F.2d at 973 
(“Consideration of costs . . . would be flatly incon- 
sistent with the statute, legislative history and case law 
on this point”); NRDC v. EPA, 824 F.2d 1146, 1158-59 
(D.C. Cir. 1987) (in banc) (“Vinyl Chloride”) (“[S]tatute 
on its face does not allow consideration of technological 
or economic feasibility. . . . Congress considered the 

20a 

alternatives and chose to close down sources or even 
industries rather than to allow risks to health”). 

Third, though the petitioners are correct that in Lead 
Industries we interpreted § 109(b), which governs the 
setting of NAAQS, and not § 109(d), which governs the 
revising of NAAQS, we can discern no legally relevant 
difference in the two sections that would make Lead 
Industries inapplicable to § 109(d). Section 109(d)(1) 
directs the EPA to: 

complete a thorough review of the criteria published 
under section 7408 of this title and the [NAAQS] 
promulgated under this section and [to] make such 
revisions in such criteria and standards and promul- 
gate such new standards as may be appropriate in 
accordance with section 7408 of this title and 
subsection (b) of this section. 

42 U.S.C. § 7409(d)(1). The petitioners contend that 
consideration of costs is one pertinent factor in deter- 
mining whether revision of a NAAQS is “appropriate,” 
but this argument ignores the clause immediately fol- 
lowing “appropriate,” which incorporates § 109(b) and 
thereby affirmatively precludes consideration of costs 
in revising NAAQS. Section 108(b), 42 U.S.C. § 7408(b), 
does require the EPA to provide the States with 
information on the cost of implementing NAAQS, but 
the reference to § 108 does not permit consideration of 
costs in setting NAAQS because it clearly relates back 
to the requirement that the EPA “make . . . revisions 
in [“the criteria published under section 7408”] . . . as 
may be appropriate.” And insofar as the air quality 
criteria do apply to the setting of NAAQS, they do so 
through § 109(b), which (again) precludes the considera- 
tion of costs and which is explicitly incorporated into 

21a 

§ 109(d)(1). See id. § 7409(b)(1) (primary NAAQS to be 
“based on [the air quality] criteria” issued under § 108). 

Fourth, the petitioners point to § 109(d)(2), which 
creates the CASAC and requires it to advise the EPA 
about, among other things, “any adverse public health, 
welfare, social, economic, or energy effects which may 
result from various strategies for attainment and main- 
tenance of such [NAAQS].” Id. § 7409(d)(2)(C)(iv). 
Why, ask the petitioners, would the CASAC be re- 
quired to advise the EPA about these matters if the 
EPA were not then supposed to consider its advice in 
the course of revising the NAAQS? As above, how- 
ever, the petitioners overlook that § 109(d)(1) directs 
the EPA to review and to revise, as appropriate, the air 
quality standards issued under § 108 as well as the 
NAAQS promulgated under § 109(b). The advice re- 
quired in § 109(d)(2)(C)(iv) is pertinent only to the 
EPA’s duty under § 108 to provide the States with 
control strategy information. 

B. Environmental Consequences of Implementing 

NAAQS 

The State Petitioners argue that the EPA erred in 
failing “to consider the environmental consequences 
resulting from the financial impact of the [revised PM2.5 
and ozone NAAQS] on the federal Abandoned Mine 
Reclamation Fund Act.” This argument is squarely 
foreclosed by our decision in NRDC. In reviewing the 
EPA’s previous revision of the PM NAAQS, we 
rejected the argument that the EPA “erred in refusing 
to consider the health consequences of unemployment 
in determining the primary [NAAQS] for particulate 
matter” and held that “[i]t is only health effects relating 
to pollutants in the air that EPA may consider.” 902 

22a 

F.2d at 972-73 (emphasis in original). Unlike the 
positive health benefits of ozone that we hold (in Part 

III.B, below) the EPA must consider, any detrimental 
health effects resulting from the financial impact upon 
the mine fund, like the health consequences of unem- 
ployment, are traceable to the cost of complying with 
the revised PM2.5 and ozone NAAQS and not to the 
presence of those pollutants in the air. 

C. The National Environmental Policy Act 

In challenging both the revised PM2.5 and ozone 
NAAQS, the State Petitioners also argue that the EPA 
failed to comply with certain requirements of the 
NEPA. The petitioners recognize that the Congress 
has exempted all actions under the Clean Air Act, 
including the setting of NAAQS, from the central 
requirement of the NEPA, namely, the preparation of 
an Environmental Impact Statement. Compare 42 
U.S.C. § 4332(2)(C)-(D) (agency must prepare EIS in all 
“major Federal actions significantly affecting the 
quality of the human environment”), with 15 U.S.C. 
§ 793(c)(1) (“No action taken under the Clean Air Act 
shall be deemed a major Federal action significantly 
affecting the quality of the human environment within 
the meaning of the [NEPA]”). Nonetheless, they sug- 
gest that the EPA is required to complete the func- 
tional equivalent of an EIS and also to comply with 
other requirements in the NEPA, see 42 U.S.C. 
§ 4332(2)(B), (E), (G). State Petitioners’ PM Brief at 20; 
State Petitioners’ Ozone Brief at 19. We reject each of 
these suggestions. 

First, the State Petitioners contend that this court 
has “recognized that the ‘[CAA], properly construed, 
requires the functional equivalent of a NEPA impact 

23a 

statement,’ ” id. (quoting Portland Cement Ass’n v. 
Ruckelshaus, 486 F.2d 375, 384 (1973)). Our decision in 
Portland Cement, however, actually construed only 
“section 111 of the Clean Air Act.” By replacing these 
words with “[CAA]” in their briefs, the petitioners 
misrepresent our interpretation of a single section of 
the Clean Air Act, dealing with emission standards for 
stationary sources, as an interpretation of the entire 
Act. Even if the petitioners were correct, however, 
Portland Cement predated, and is now superseded by, 
the statutory exemption in 15 U.S.C. § 793(c)(1), which 
the Congress added in 1974. 

Second, the State Petitioners contend that a pro- 
vision of the NEPA “requires that EPA weigh ‘eco- 
nomic considerations.’ ” 

The section to which the 
petitioners refer reads as follows: “all agencies of the 
Federal Government shall . . . identify and develop 
methods and procedures . . . which will insure that 
presently unquantified environmental amenities and 
values may be given appropriate consideration in 
decisionmaking along with economic and technical 
considerations.” 42 U.S.C. § 4332(2)(B). Even if this 
section is properly read generally to require an agency 
to consider implementation costs, § 109(d)(1) specifi- 
cally prohibits the EPA from doing so. And the NEPA 
provides that it shall not “in any way affect the specific 
statutory obligations of any Federal agency . . . to 
comply with criteria or standards of environmental 
quality.” 42 U.S.C. § 4334(1). Therefore, § 4332(2)(B) 
cannot require the EPA to disregard the prohibition in 
§ 109(d)(1) upon the consideration of costs in setting 
NAAQS. 

24a 

The State Petitioners’ remaining arguments—that 
the EPA failed to comply with two other sections of the 
NEPA—fare little better. Section 4332(2)(E) requires 
federal agencies to “study, develop, and describe appro- 
priate alternatives to recommended courses of action in 
any proposal which involves unresolved conflicts con- 
cerning alternative uses of available resources.” As 
with § 4332(2)(B), insofar as § 4332(2)(E) can be read to 
require the EPA to consider the costs of implementing 
NAAQS when revising those standards, contrary to the 
prohibition in § 109(d)(1), § 4334(1) prevents it from 
having any effect. 

If, on the other hand, § 4332(2)(E) is understood in 
the context of the Clean Air Act to require the EPA 
merely to discuss implementation alternatives, then it, 
like the similar § 4332(2)(G) with which the petitioners 
also claim the EPA failed to comply, is the functional 
equivalent of § 108(b)(1). That section requires the 
EPA to provide the States with, among other things, 
“such data as are available on available technology and 
alternative methods of prevention and control of air 
pollution.” As we recognize with regard to the require- 
ment that the agency prepare an EIS, “[c]ompliance 
with NEPA’s . . . requirement[s] has not been con- 
sidered necessary when the agency’s organic legislation 
mandates procedures for considering the environment 
that are ‘functional equivalents’ of the [NEPA’s] 
process.” Izaak Walton League of Am. v. Marsh, 655 
F.2d 346, 367 n.51 (1981). The rationale for the func- 
tional equivalence doctrine is the well-established prin- 
ciple that a “general statutory rule usually does not 
govern unless there is no more specific rule.” Green v. 
Bock Laundry Mach. Co., 490 U.S. 504, 524 (1989); see 
also Alabama ex rel. Siegelman v. EPA, 911 F.2d 499, 

25a 

504-05 (11th Cir. 1990) (citing cases). The NEPA is the 
general statute requiring agencies to consider environ- 
mental harms, whereas the Clean Air Act is the more 
specific and its equivalent provisions apply in place of 
those in the NEPA. See Portland Cement, 486 F.2d at 
386 (finding functional equivalence when more specific 
statute strikes “workable balance between some of the 
advantages and disadvantages of full application of 
NEPA”). 

Our analysis of the petitioners’ contentions leads us 
to conclude that nothing in the NEPA requires the 
EPA in setting NAAQS to consider or to discuss 
matters that the Clean Air Act does not already permit 
or require. 

D. The Unfunded Mandates Reform Act 

The State Petitioners in the particulate matter case 
and Congressman Bliley in the ozone case both contend 
that the EPA is required by the Unfunded Mandates 
Reform Act, 2 U.S.C. § 1501 et seq., to prepare a Regu- 
latory Impact Statement (RIS) when setting a NAAQS, 
see id. § 1532, and to choose the least burdensome from 
a range of alternative permissible NAAQS, see id. 
§ 1535. Even if the petitioners and the amicus are 
correct regarding the interaction of the UMRA and the 
CAA—a point the EPA strongly contests—we can pro- 
vide them with no relief. See id. § 1571(a)(3) (“[T]he 
inadequacy or failure to prepare [a RIS] . . . shall not 
be used as a basis for staying, enjoining, invalidating or 
otherwise affecting [an] agency rule”); id. § 1571(b) 
(“Except as provided in [§ 1571(a), which does not 
mention § 1535,] . . . any compliance or noncompliance 
with the provisions of this chapter . . . shall not be 
subject to judicial review; and no provision of this 

26a 

chapter shall be construed to [be] . 
. . enforceable by 

any person in any . . . judicial action”). 

The State Petitioners, recognizing the limitations 
upon judicial review in § 1571, contend that the EPA’s 
failure to prepare a RIS can nonetheless render 
the NAAQS arbitrary and capricious, see 42 U.S.C. 
§ 7607(d)(9), relying upon Thompson v. Clark, 741 F.2d 
401 (D.C. Cir. 1984). In that case, we interpreted a 
statute that, like the UMRA, both specified that the 
RIS be included in the record for judicial review and 
precluded judicial review of an agency’s compliance 
with the RIS requirement. We held that a “reviewing 
court will consider the contents of the [RIS], along with 
the rest of the record, in assessing not the agency’s 
compliance with the [requirement to prepare the RIS], 
but the validity of the rule under other provisions of 
law.” Id. at 405. No information in a RIS, however, 
could lead us to conclude that the EPA improperly set 
the PM and ozone NAAQS; the only information such a 
statement would add to the rulemaking record for a 
NAAQS would pertain to the costs of implementation, 
see 2 U.S.C. § 1532(a), and the EPA is precluded from 
considering those costs in setting a NAAQS. Accord- 
ingly, the failure to prepare a RIS does not render the 
NAAQS arbitrary and capricious. 

E. The Regulatory Flexibility Act 

In both the ozone and particulate matter cases, the 
Small Business Petitioners argue that the EPA im- 
properly certified that the revised NAAQS would not 
have a significant impact upon a substantial number of 
small entities. The Regulatory Flexibility Act, 5 U.S.C. 
601 et seq., as amended in 1996 by the Small Business 
Regulatory Enforcement Fairness Act, Pub. L. No. 

27a 

104-121, tit. II, 110 Stat. 857-74 (“SBREFA”), requires 
an agency, when engaging in notice and comment rule- 
making, to “prepare and make available for public 
comment an initial regulatory flexibility analysis. . . . 

[that] describe[s] the impact of the proposed rule on 
small entities,” 5 U.S.C. § 603(a), including small busi- 
nesses, small organizations, and small governmental 
jurisdictions, see id. § 601(6). When promulgating a 
final rule, an agency must describe “the steps . . . 
taken to minimize the significant economic impact on 
small entities.” Id. § 604(a)(5). According to the peti- 
tioners, if the EPA had complied with the RFA, it 
would likely have promulgated less stringent PM and 
ozone NAAQS than those actually chosen, which would 
have reduced the burden upon small entities. 

A regulatory flexibility analysis is not required, 
however, if the agency “certifies that the rule will not, if 
promulgated, have a significant economic impact on a 
substantial number of small entities.” Id. § 605(b). 
Further, the SBREFA made no change in the require- 
ment that a regulatory flexibility analysis conducted 
pursuant to the RFA include estimates of “the number 
of small entities to which the proposed rule will apply” 
and of “the classes of small entities which will be sub- 
ject to the requirement.” 5 U.S.C. § 603(b)(3)-(4). We 
have consistently interpreted the RFA, based upon 
these sections, to impose no obligation upon an agency 
“to conduct a small entity impact analysis of effects on 
entities which it does not regulate.” Motor & Equip. 
Mfrs. Ass’n v. Nichols, 142 F.3d 449, 467 & n.18 (1998). 

The EPA certified that its revised NAAQS will “not 
have a significant economic impact on small entities 
within the meaning of the RFA.” PM Final Rule, 62 

28a 

Fed. Reg. at 38,702/2; Ozone Final Rule, 62 Fed. Reg. at 
38,887/2-3. According to the EPA, the NAAQS them- 
selves impose no regulations upon small entities. In- 
stead, the several States regulate small entities 
through the state implementation plans (SIPs) that 
they are required by the Clean Air Act to develop. See 
42 U.S.C. § 7410. Because the NAAQS therefore regu- 
late small entities only indirectly—that is, insofar as 
they affect the planning decisions of the States—the 
EPA concluded that small entities are not “subject to 
the proposed regulation.” See Mid-Tex Elec. Coop., 
Inc. v. FERC, 773 F.2d 327, 342 (D.C. Cir. 1985); see 
also id. at 343 (“Congress did not intend to require that 
every agency consider every indirect effect that any 
regulation might have on small businesses in any 
stratum of the national economy.”). 

The EPA’s description of the relationship between 
NAAQS, SIPs, and small entities strikes us as incon- 
testable. The States have broad discretion in deter- 
mining the manner in which they will achieve compli- 
ance with the NAAQS. The EPA “is required to 
approve a state plan which provides for the timely 
attainment and subsequent maintenance of ambient air 
standards” and cannot reject a SIP based upon its view 
of “the wisdom of a State’s choices of emission limita- 
tions,” Train v. NRDC, 421 U.S. 60, 79 (1975) (emphasis 
in original), or of the technological infeasibility of the 
plan. See Union Elec. Co. v. EPA, 427 U.S. 246, 265 
(1976). Therefore, a State may, if it chooses, avoid 
imposing upon small entities any of the burdens of 
complying with a revised NAAQS. Only if a State does 
not submit a SIP that complies with § 110, 42 U.S.C. 
§ 7410, must the EPA adopt an implementation plan of 
its own, which would require the EPA to decide what 

29a 

burdens small entities should bear. The agency has 
stated, however, that it will do a regulatory flexibility 
analysis before adopting an implementation plan of its 
own, as it did in 1994 when proposing such a plan for 
Los Angeles. See Ozone Final Rule, 62 Fed. Reg. at 
38,891/1; PM Final Rule, 62 Fed. Reg. at 38,705/3. 

The responses of the Small Business Petitioners do 
not persuade us to reject the EPA’s argument or to 
deviate from our holdings in Mid-Tex and its progeny. 
First, the Small Business Petitioners contend that we 
must defer to the Small Business Administration’s 
interpretation of the Act, as expressed in a letter to the 
EPA from the SBA’s Chief Counsel for Advocacy, that 
the NAAQS do impose requirements upon small 
entities. The SBA, however, neither administers nor 
has any policymaking role under the RFA; at most its 
role is advisory. See, e.g., 5 U.S.C. §§ 601(3), 602(b), 
603(a), 605(b), 609(b)(1), 612. Therefore, we do not 
defer to the SBA’s interpretation of the RFA. See 
Scheduled Airlines Traffic Offices, Inc. v. Department 
of Defense, 87 F.3d 1356, 1361 (D.C. Cir. 1996) (no 
Chevron deference owed to agency interpretation of 
statute it does not administer). Nor do we defer to the 
EPA’s interpretation of the RFA, for it does not 
administer the Act either. We do, however, find the 
EPA’s interpretation of the statute persuasive. 

Second, the Small Business Petitioners argue that 
the EPA cannot claim both that the NAAQS will have 
no effect upon small entities and that it will have posi- 
tive health effects. Clearly, however, the EPA can 
maintain that the NAAQS will have health effects 
because the Clean Air Act empowers the agency to 
ensure that such benefits accrue; and it can maintain 

30a 

that the NAAQS will not directly affect small entities 
because it has no authority (short of imposing its own 
implementation plan upon a non-complying state) to 
impose any burdens upon such entities. 

The Small Business Petitioners attempt to distin- 
guish the possible effects upon small entities in this 
case from the indirect effects that, as we found in Mid- 
Tex, are not within the contemplation of the RFA. But 
Mid-Tex is not so easily distinguished. The petitioners 
in that case argued that the RFA required the FERC 
to consider economic effects not only upon regulated 
industries but also upon the small entities that are their 
wholesale customers, even though the customers were 
not directly regulated by the FERC. We rejected that 
argument, finding a “clear indication” in the language of 
§ 603 that the RFA is “limited to small entities subject 
to the proposed regulation.” Mid-Tex, 773 F.2d at 342; 
see also Motor & Equip. Mfrs. Ass’n, 142 F.3d at 467 

n.18 (“The RFA itself distinguishes between small 
entities subject to an agency rule, to which its require- 
ments apply, and those not subject to the rule, to which 
the requirements do not apply.”); United Distribution 
Cos. v. FERC, 88 F.3d 1105, 1170 (1996) (regulatory 
flexibility analysis provision applies only to “small enti- 
ties that are subject to the requirements of the rule”) 
(emphasis in original). That the Clean Air Act requires 
the States to submit SIPs that will achieve compliance 
with the NAAQS does not, in view of the States’ nearly 
complete discretion to determine which entities will 
bear the burdens of a revised NAAQS, make such small 
entities as the SIPs may regulate any more subject to 
the EPA’s regulation than were the wholesalers in 
Mid-Tex subject to regulation by the FERC. 

31a 

Finally, the Small Business Petitioners suggest that 
the Congress in enacting the SBREFA overruled our 
prior interpretation of the RFA in Mid-Tex and its 
progeny. The SBREFA made a number of changes in 
the RFA, but it did not change anything in § 603 upon 
which we relied in Mid-Tex. And although the Congress 
made a slight modification in § 605(b), we do not under- 
stand it to alter our analysis in Mid-Tex. Prior to 1996, 
§ 605(b) required an agency to provide “a succinct 
statement explaining the reasons” for its certification 
that the promulgated rule would not have a significant 
economic impact upon small entities. That section now 
requires “a statement providing the factual basis for 
such certification.” Our decision in Mid-Tex contem- 
plates that an agency may justify its certification under 
the RFA upon the “factual basis” that the rule does not 
directly regulate any small entities. Nothing in the 
change to § 605(b) suggests that basis for certification is 
no longer permissible. (Indeed, the section of the stat- 
ute amending § 605(b) is labeled “Technical and Con- 
forming Amendments,” see SBREFA § 243, 110 Stat. at 
866.) We therefore conclude that the EPA properly 
certified that its NAAQS would not have a significant 
impact upon a substantial number of small entities. 

III. Ozone 

A. Subpart 2 and the Revised Ozone Standard 

In 1990 the Congress substantially revised the Clean 
Air Act by, among other things, adding specific enforce- 
ment provisions for carbon monoxide, particulate mat- 
ter, sulfur oxides, nitrogen dioxide, lead, and as perti- 
nent here, ozone. Previously, the Act required that all 
areas of the country not attaining the primary ozone 
standard, no matter how far from attainment, come into 

32a 

compliance “as expeditiously as practicable but not 
later than December 31, 1987.” 42 U.S.C. § 7502 (1988). 
Many areas had not attained the primary ozone 
NAAQS by that date; some were still a long way from 
doing so. The Congress responded to the continued 
ozone problem by enacting a new enforcement scheme, 
which it codified as Subpart 2 of Part D of the Clean Air 
Act, 42 U.S.C. §§ 7511-7511f, redesignating the original 
provisions as Subpart 1. 

Subpart 2 requires the EPA to classify nonattain- 
ment areas based upon their design value, which is a 
rough measure of whether an area complies with the 

0.12 ppm, 1-hour primary ozone standard.6 A table in 

6 More specifically, the design value is the fourth-highest daily 
maximum ozone concentration in an area over three consecutive 
years for which there are sufficient data. If that value is less than 
or equal to 0.12 ppm, then an area will have only three expected 
values above that level and it will be in attainment with the ozone 
NAAQS. See EPA, The Clean Air Act Ozone Design Value Study: 
Final Report 1-1 to 1-22 (1994) (filed pursuant to 42 U.S.C. 
§ 7511b(g), which required the EPA to conduct “a study of whether 
the [existing design value] methodology . . . provides a 
reasonable indicator of the ozone air quality of ozone nonattain- 
ment areas”; the EPA concluded it did). 

33a 

Subpart 2, set out here in the margin,7 establishes 
classifications ranging from marginal to extreme, and 
provides an attainment date for each class. See id. § 
7511(a)(1)-(2). Subpart 2 also specifies, for each class of 
nonattainment areas, both measures that the States 
must take to reduce emissions of the chemicals that are 
precursors of ozone and information that the States 
must report to the EPA. See id. § 7511a. In short, 
Subpart 2 is the Congress’s comprehensive plan for 
reducing ozone levels throughout the country. 

The State and Non-State Petitioners, along with 
Congressman Bliley appearing as an amicus curiae, 

7 This table appears in Clear Air Act § 181(a)(1), 42 U.S.C. § 
7511(a)(1): 

TABLE 1 

___________________________________________________________ 

Area Class 
Design value [ppm] 

Primary standard 

attainment date 

___________________________________________________________ 

Marginal . . . . . . . . 
0.121 up to 0.138 . . . . . . . 

3 years after 

November 15, 1990 

Moderate . . . . . . . 
0.138 up to 0.160 . . . . . . . 

6 years after 

November 15, 1990 

Serious . . . . . . . . . 
0.160 up to 0.180 . . . . . . 

.9 years after 

November 15, 1990 

Severe . . . . . . . . . 
0.180 up to 0.280 . . . . . . . 

15 years after 

November 15, 1990 

Extreme . . . . . . . . 
0.280 and above . . . . . . . . 20 years after 

November 15, 1990 

The Severe Area category is later subdivided, creating a sixth 
classification for ozone nonattainment areas. See id. § 7511(a)(2) 
(“Notwithstanding table 1, [for] a severe area with a 1988 ozone 
design value between 0.190 and 0.280 ppm, the attainment date 
shall be 17 years . . . after November 15, 1990”). 

34a 

argue that Subpart 2 precludes the EPA from revising 
the primary and secondary ozone NAAQS. We reject 
this argument (in Part III.A.1) insofar as it pertains to 
the EPA’s continued ability to promulgate a revised 
ozone NAAQS or to designate areas as not in attain- 
ment with a revised NAAQS. We agree (in Part 

III.A.2) with those petitioners, however, insofar as they 
maintain, based upon the text and structure of Sub- 
parts 1 and 2, that the EPA is precluded from enforcing 
a revised primary ozone NAAQS other than in accor- 
dance with the classifications, attainment dates, and 
control measures set out in Subpart 2. Further, we 
conclude (in Part III.A.3) that the EPA may not re- 
quire a State to comply with a revised secondary ozone 
NAAQS in any area that has yet to attain the 0.12 ppm 
primary standard. 

1. The EPA’s Power to Revise the Ozone NAAQS and 
Designate Areas as Nonattainment 

The 1990 amendments did not alter the section of the 
Clean Air Act that provides for setting and revising 
primary and secondary NAAQS. See 42 U.S.C. § 7409. 
The Administrator, therefore, still must “at five-year 
intervals [from December 31, 1980] . . . complete a 
thorough review of . . . the [NAAQS] promulgated 
under this section and . . . make such revisions in such 

. . . standards . . . as may be appropriate.” Id. 
§ 7409(d)(1). The Second Circuit held that this section 
continues to “set[ ] forth a bright-line rule for agency 
action,” American Lung Ass’n v. Reilly, 962 F.2d 258, 
263 (1992), and we agree. Nothing in the Act modifies 
this “bright-line rule” or otherwise makes it inapplica- 
ble to revision of the ozone NAAQS. 

35a 

To the extent that the 1990 amendments shed any 
light upon this question, they suggest that the EPA 
retains its authority to revise the ozone NAAQS. For 
example, if the EPA relaxes a NAAQS after enactment 
of the 1990 amendments, then “the Administrator shall 

. . . promulgate requirements applicable to all areas 
which have not attained that [relaxed] standard as of 
the date of such relaxation. . . . [which] shall provide 

for controls . . . not less stringent than the controls 
applicable to areas designated nonattainment before 
such relaxation.” 42 U.S.C. § 7502(e). Although two 
other subsections of § 172 are expressly made inapplica- 
ble to the ozone regulations in Subpart 2, see id. § 
7502(a)(1)(C), (a)(2)(D), this so-called anti-backsliding 
provision contains no such exemption. Accordingly, as 
the EPA notes, this section specifically contemplates 
that the agency may relax its ozone NAAQS and, there- 
fore, necessarily implies that it retains the authority to 
revise that NAAQS. Tellingly, neither the petitioners 
nor the amicus reply to this point. 

The petitioners and amicus raise two other argu- 
ments to support their position that the EPA cannot 
alter the ozone NAAQS without the approval of the 
Congress. We reject both in short order. 

First, the Non-State Petitioners contend that Sub- 
part 2 renders revision of the ozone NAAQS “inappro- 
priate” within the meaning of § 109(d)(1), which pro- 
vides the EPA shall “make such revisions in such . . . 
standards . . . as may be appropriate.” 42 U.S.C. 
§ 7409(d)(1). This argument, however, pointedly ig- 
nores the text immediately following the word “ap- 
propriate,” which specifies that appropriateness is to be 
determined “in accordance with section 7408 . . . and 

36a 

[§ 7409(b)]” (and which, as we read it, means exclu- 
sively in accord with those sections). See, e.g., Ameri- 
can Methyl Corp. v. EPA, 749 F.2d 826, 835-36 (D.C. 
Cir. 1984). Because Subpart 2 is neither listed in § 
109(d)(1) nor incorporated by reference in either § 108, 
id. § 7408, or §109(b), it cannot render revision of the 
ozone NAAQS inappropriate. 

Second, the State Petitioners and Congressman 
Bliley argue, based upon the classification table in § 
181(a)(1), id. § 7511(a)(1), that Subpart 2 codified the 

0.12 ppm ozone NAAQS and, therefore, only the Con- 
gress can promulgate a revised NAAQS. Yet not all 
areas designated nonattainment for ozone will have 
design values of 0.121 ppm or higher. In fact, this was 
true of areas designated nonattainment for ozone as a 
result of the 1990 amendments, see Ozone Final Rule, 
62 Fed. Reg. at 38,884/3, at least in part because of the 
stringent criteria in the Clean Air Act for changing the 
designation of an area to attainment from nonattain- 
ment. See 42 U.S.C. § 7407(d)(3)(E)(iii) (redesignation 
permissible only if area’s attainment of NAAQS “is due 
to permanent and enforceable reductions in emissions”). 
In short, although the numbers in the classification 
table are based upon the 0.12 ppm ozone NAAQS, they 
are neither equivalent to nor a codification of the 
NAAQS. 

Not only does the EPA, as we conclude above, retain 
authority to promulgate a revised ozone NAAQS; the 
agency is still required, “in no case later than 2 years 
from the date of promulgation” of a revised NAAQS, to 
designate areas as attainment, nonattainment, or 
unclassifiable under that NAAQS. Id. § 7407(d)(1)(B). 
Although the 1990 amendments extended by roughly 18 

37a 

months the maximum time between promulgation of a 
revised NAAQS and designation of nonattainment 
areas under that NAAQS, see 42 U.S.C. § 7407(d)(1)-(2) 
(1988), they made no substantive change in the EPA’s 
authority to designate areas as nonattainment under a 
revised NAAQS. Therefore, we hold that the EPA 
retains the power to designate areas as nonattainment 
under a revised ozone NAAQS. 

2. The EPA’s Power to Enforce the Revised Ozone 
Standard 

That the enactment of Subpart 2 does not alter the 
EPA’s authority to revise the ozone NAAQS or to 
designate areas as nonattainment for ozone does not, 
however, compel the conclusion that Subpart 2 has no 
effect upon the EPA’s authority to enforce a revised 
primary ozone NAAQS (We consider the enforcement 
of secondary ozone NAAQS in Part III.A.3, below.) In 
fact, the text and structure of Subparts 1 and 2 suggest 
precisely the opposite conclusion. After designating an 
area as nonattainment under a NAAQS, the EPA 
normally looks to Subpart 1 for authority to “classify 
the area for the purpose of applying an attainment 
date.” 42 U.S.C. § 7502(a)(1)-(2). The cited provisions, 
however, do not apply “with respect to nonattainment 
areas for which classifications [and attainment dates] 
are specifically provided under other provisions of 
[Part D of Subchapter 1 of the Clean Air Act].” Id. § 
7502(a)(1)(C), (a)(2)(D). 

The EPA argues that Subpart 2 specifically provides 
classifications and attainment dates only for nonattain- 
ment designations under the 0.12 ppm ozone NAAQS. 

38a 

The State and Non-State Petitioners counter that 
Subpart 2 specifically provides classifications and dates 
for all areas designated nonattainment under any ozone 
NAAQS. We agree with the petitioners. 

The pertinent provision of Subpart 2 reads as follows: 

(a) Classification and attainment dates for 1989 
nonattainment areas. - (1) Each area designated 
non-attainment for ozone pursuant to section 
7407(d) of this title shall be classified at the time of 
such designation, under table 1, by operation of law, 
as a Marginal Area, a Moderate Area, a Serious 
Area, a Severe Area, or an Extreme Area. . . . 

Id. § 7511(a)(1). As the petitioners note, § 107(d), 42 
U.S.C. § 7407(d), specifies three different times at 
which an area can be designated “nonattainment for 
ozone”: immediately following enactment of the 1990 
amendments, id. § 7407(d)(4); after the EPA revises the 
ozone NAAQS, id. § 7407(d)(1); and when an area that 
was in attainment, either when the Congress enacted 
the 1990 amendments or when the EPA promulgated a 
revised ozone NAAQS, later ceases to comply, id. § 
7407(d)(3). The petitioners conclude from the general 
reference to § 107(d) that the classifications and attain- 
ment dates in Subpart 2 apply to areas designated 
under §§ 107(d)(1), (3), and (4). The EPA gamely 
responds that the reference to § 107(d) includes only 
subsection (4), but we do not defer to the agency’s 
interpretation because we find that the Congress has 
spoken on the “precise question at issue” and we “must 
give effect to the unambiguously expressed intent of 
Congress.” Chevron U.S.A. Inc., 467 U.S. 837, 842-43 & 

n.9 (1984). We canvass the two reasons that lead us to 

39a 

this conclusion before returning to the EPA’s argu- 
ment. 

First, the reference to § 107(d) in § 181(a)(1) appears 
to have been purposeful and not the drafting error that 
the EPA’s interpretation implies. The Congress con- 
sidered but did not adopt bills that clearly would have 
limited the reach of Subpart 2 to nonattainment desig- 
nations made immediately following enactment of the 
1990 amendments. The Senate bill contained a version 
of Subpart 2 that classified only those areas designated 
nonattainment for ozone under its equivalent of 
§ 107(d)(4). See S. 1630, 101st Cong. §§ 101, 107, re- 
printed in III Legislative History of the Clean Air Act 
Amendments of 1990, at 4124-25, 4195 [hereinafter 1990 
Legislative History]. The version of Subpart 2 in the 
House bill, as originally introduced, similarly referred 
only to designations made under its equivalent of § 
107(d)(4). See H.R. 3030, 101st Cong. §§ 101(a), 103, 
reprinted in II 1990 Legislative History, at 3748-49, 
3795-96 The House committee, however, replaced the 
specific reference to what is now § 107(d)(4) with a 
general reference to § 107(d). See H.R. Rep. No. 101- 
490, at 3-6, 17 (1990), reprinted in II 1990 Legislative 
History, at 3027-30, 3041. The Conference committee 
then reported the text of the House bill rather than 
that of the Senate. See H.R. Rep. No. 101-952, at 335 
(1990), reprinted in I 1990 Legislative History, at 1785. 

Second, our conclusion that the Congress intention- 
ally referred to § 107(d) as a whole is supported by a 
comparison of Subparts 1 and 2. The Congress enacted 
Subpart 2 because of the failure of the controls in 
Subpart 1 to bring areas into attainment with the 0.12 
ppm standard in the allotted time. See H.R. Rep. No. 

40a 

101-490, at 145-50, reprinted in II 1990 Legislative 
History, at 3169-74. Rather than continue treating all 
ozone nonattainment areas alike, the Congress allowed 
the various areas between 3 and 20 years to attain the 
ozone NAAQS, depending upon the extent of the area’s 
ozone problem. See id. at 146-47 (“In 1977, Congress 
tried to waive [sic] a ‘magic wand’ and command that all 
nonattainment areas [for ozone] will meet the applica- 
ble [NAAQS]. . . . by December 31, 1987. . . . [That] 

date[ ] ha[s] come and gone and it is clear that ... we had 
no ‘magic’ solutions.”), reprinted in II 1990 Legislative 
History, at 3170-71. As the petitioners argue, because 
the 1990 amendments extended the time for nonattain- 
ment areas to comply with the 0.12 ppm ozone NAAQS, 
they must preclude the EPA from requiring areas to 
comply either more quickly or with a more stringent 
ozone NAAQS. 

Subpart 1 requires compliance with a primary 
NAAQS “as expeditiously as practicable, but no later 
than 5 years from the date such area was designated 
nonattainment.” 42 U.S.C. § 7502(a)(2)(A). All non- 
attainment areas would have until 2012 to comply with 
the revised ozone NAAQS if the EPA and the States 
were to take the full time authorized in Subpart 1 for 
making attainment designations and the EPA were to 
approve every possible extension for each area. See id. 
§§ 7407(d)(1)(A)-(B), 7502(a)(2)(A), (C). Such wide 
discretion is inconsistent, however, with Subpart 2, in 
which the Congress stripped the EPA of discretion to 
decide which ozone nonattainment areas should receive 
more time to reach attainment (with two limited excep- 
tions not relevant here, see id. § 7511(a)(4), (5)). 
Moreover, under § 181(a) of Subpart 2, Los Angeles, the 
nation’s only Extreme Area, has until 2010 to attain the 

41a 

0.12 ppm ozone NAAQS, and the possibility of extend- 
ing that deadline until 2012. That Los Angeles should 
also have to attain a more stringent ozone standard by 
that same year, if not earlier, clearly runs counter to 
the comprehensive enforcement scheme enacted in Sub- 
part 2. 

The EPA offers two arguments against this interpre- 
tation of Subparts 1 and 2. First, the EPA contends 
that a recent statute confirms its power to designate 
nonattainment areas under the revised ozone standard. 
See Pub. L. No. 105-178, § 6103(a), 112 Stat. 465 (1998) 
(extending time to two years from one year for gov- 
ernor to submit proposed designation under 0.08 ppm 
ozone NAAQS). That statute also specifically states, 
however, that “[n]othing in section[ ] . . . 6103 shall be 
construed by the Administrator of Environmental Pro- 
tection Agency or any court . . . to affect any pending 
litigation or to be a ratification of the ozone . . . 
standard[ ].” Id. § 6104. Further, even if the EPA were 
correct that § 6103 confirms the agency’s power to 
designate areas under a revised ozone NAAQS, that 
power was never in doubt, as we concluded above. 
Indeed, § 6104 simply does not bear upon the question 
we address here: whether Subpart 1 or Subpart 2 
provides the applicable enforcement mechanisms for an 
area designated nonattainment under a revised ozone 
NAAQS. 

Second, the EPA argues that read in context the 
reference to § 107(d) in § 181(a)(1) relates only to des- 
ignations made under § 107(d)(4). Because the table in 
§ 181(a)(1) classifies areas based upon a design value 
that roughly measures attainment of the 0.12 ppm 
ozone NAAQS, the EPA contends that the nonattain- 

42a 

ment designations referenced in § 181(a)(1) are only 
those designations made under the 0.12 ppm ozone 
NAAQS. This explanation, however, does not square 
with either the Congress’s decision not to refer to 
§ 107(d)(4) specifically or the long-term nature of the 
attainment scheme enacted in Subpart 2; on the EPA’s 
interpretation, that scheme would have been stillborn 
had the EPA revised the ozone NAAQS immediately 
after the Congress enacted the 1990 amendments. 

The EPA points next to § 181(b)(1), which specifies 
the attainment dates for areas that met the 0.12 ppm 
standard when the Congress enacted the 1990 amend- 
ments but that later cease to comply. That section, 
however, applies only to areas designated under 
§ 107(d)(3) that previously were “designated attainment 
or unclassifiable for ozone under section [107(d)(4)].” 
That § 181(b)(1) provides special rules for such areas, 
but not for areas designated under § 107(d)(3) that had 
previously been designated attainment for ozone or 
unclassifiable under § 107(d)(1), does not support the 
EPA’s argument that the phrase in § 181(a)(1) “desig- 
nated nonattainment for ozone pursuant to section 
107(d)” denotes only those designations made under 
§ 107(d)(4). If anything, the specification of § 107(d)(4) 
in § 181(b)(1) makes its absence from § 181(a)(1) all the 
more striking. 

The final bit of context to which the EPA points is 
the title of § 181(a): “Classification and attainment 
dates for 1989 nonattainment areas.” Because the title 
specifies “1989 nonattainment areas,” we are told, 
§ 181(a) must refer only to nonattainment designations 
made immediately after enactment of the 1990 amend- 
ments, that is, designations made under § 107(d)(4). 

43a 

Although “the title of a statute or section can aid in 
resolving an ambiguity in the legislation’s text,” INS v. 
National Ctr. for Immigrants’ Rights, Inc., 502 U.S. 
183, 189 (1991), a title cannot be allowed to create an 
ambiguity in the first place. See Maguire v. Commis- 
sioner of Internal Revenue, 313 U.S. 1, 9 (1941) (“[T]he 
title of an act will not limit the plain meaning of the 
text.”). The text of § 181(a) clearly encompasses non- 
attainment designations made under all subsections of 
§ 107(d). There simply is no ambiguity in need of 
resolution by reference to the title of the section. 

In sum, § 181(a) “specifically provide[s]” for classifi- 
cations and attainment dates for areas designated non- 
attainment for ozone pursuant to § 107(d)(1). Accord- 
ingly, Subpart 2, not Subpart 1, provides the classifica- 
tions and attainment dates for any areas designated 
nonattainment under a revised primary ozone NAAQS, 
see 42 U.S.C. § 7502(a)(1)(C), (a)(2)(D), and the EPA 
must enforce any revised primary ozone NAAQS under 
Subpart 2. 

3. The Secondary Ozone NAAQS 

The Non-State Petitioners briefly contend that our 
conclusion that Subpart 2 provides the classifications 
and attainment dates for areas designated nonattain- 
ment under a revised primary ozone NAAQS is equally 
applicable to the enforcement of a revised secondary 
ozone NAAQS. We find it impossible to conclude, 
however, that Subpart 2 “specifically provide[s]” for 
classifications and attainment dates for areas desig- 
nated nonattainment with a revised secondary ozone 
NAAQS; § 181(a)(1) expressly refers only to primary 
NAAQS and Subpart 2 not once mentions secondary 
NAAQS. Further, attainment dates in Subpart 1 for 

44a 

secondary standards are less stringent than for primary 
standards, making comparison with the more lenient 
dates in Subpart 2 less troubling. Compare id. § 
7502(a)(2)(B) (attainment of secondary NAAQS “shall 
be . . . achieved as expeditiously as practicable after 
the date such area was designated nonattainment”), 
with id. § 7502(a)(2)(A) (attainment of primary NAAQS 
“shall be . . . achieved as expeditiously as practica- 
ble, but no later than 5 years from the date such area 
was designated nonattainment”). Nonetheless, we un- 
derstand Subpart 2 to codify the Congress’s judgment 
as to what is “as expeditiously as practicable” in reduc- 
ing an area’s level of ozone. Consequently, the EPA is 
precluded from requiring any steps toward compliance 
with a revised secondary ozone NAAQS prior to an 
area’s attainment of the 0.12 ppm standard. In areas 
that meet the 0.12 ppm standard, however, Subpart 2 
erects no bar to the EPA’s requiring compliance with a 
revised secondary ozone NAAQS “as expeditiously as 
practicable.” 

B. Ozone’s Health Benefits 

Petitioners presented evidence that according to 
them shows the health benefits of tropospheric ozone as 
a shield from the harmful effects of the sun’s ultraviolet 
rays—including cataracts and both melanoma and 
nonmelanoma skin cancers. In estimating the effects of 
ozone concentrations, EPA explicitly disregarded these 
alleged benefits. 

EPA explained its decision first as a matter of 
statutory interpretation. Under the Clean Air Act, 
EPA’s ambient standards for any pollutant are to be 
“based on [the] criteria” that EPA has published for 
that pollutant. 42 U.S.C. § 7409(b)(1) & (2). The “crite- 

45a 

ria,” in turn, are to “reflect the latest scientific knowl- 
edge 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.” Id. § 7408(a)(2). 
The reference to “all identifiable effects” would seem on 
its face to include beneficent effects. 

EPA attempts to avoid this straightforward reading 
in several ways. First, it points to the term “such 
pollutant,” arguing that the statute requires it to focus 
exclusively on the characteristics that make the sub- 
stance a “pollutant.” But the phrase “pollutant” is 
simply a label used to identify a substance to be listed 
and controlled by the statute. While it is perfectly true 
that a substance known to be utterly without adverse 
effects could not make it onto the list, this fact of 
nomenclature does not visibly manifest a congressional 
intent to banish consideration of whole classes of 
“identifiable effects.” 

EPA also relies on the fact that two of the three 
specified considerations under § 108(a)(2)’s general 
mandate refer to “adverse effect[s]”: 

The criteria for an air pollutant, to the extent 
practicable, shall include information on– 

(A) those variable factors (including atmospheric 
conditions) which of themselves or in combination 
with other factors may alter the effects on public 
health or welfare of such air pollutant; 

(B) the types of air pollutants which, when pre- 
sent in the atmosphere, may interact with such 

46a 

pollutant to produce an adverse effect on public 
health or welfare; and 

(C) any known or anticipated adverse effects on 
welfare. 

Id. § 7408(a)(2) (emphasis added). EPA’s argument 
would be of uncertain force even if all three types of 
effects specifically required to be considered were 
spoken of as “adverse effects”; there is no reason to 
read “adverse” back into the “all identifiable effects” of 
§ 108(a)(2). But as one of the three specified classes 
refers to “effects” unmodified, id. § 7408(a)(2)(A), we 
can reject EPA’s argument without even reaching that 
issue. That Congress qualified “effects” in clauses (B) 
and (C) with “adverse” seems only to strengthen the 
supposition that in (A)—and in the general mandate—it 
intended to cover all health or welfare effects. There- 
fore if petitioners’ contentions are right, clause (A) 
applies to ozone: the presence of ultraviolet radiation at 
various levels “alter[s] the effects [of ozone] on public 
health or welfare” by making them on the whole less 
malign—perhaps even beneficial. 

EPA next argues that Title VI of the Clean Air Act, 
id. §§ 7671-7671q, which mandates certain measures to 
preserve stratospheric ozone, represents a complete 
consideration of ozone’s beneficial role as a UV shield. 
Petitioners’ claim, however, is that ground-level (tropo- 
spheric) ozone—the subject of this rule—has a UV- 
screening function independent of the ozone higher in 
the atmosphere. EPA points to nothing in the statute 
that purports to address tropospheric ozone. 

Finally, EPA directs us towards legislative history 
from the 1970 and 1990 Clean Air Act Amendments. 

47a 

The “all identifiable effects” language, however, dates 
to the 1967 Amendments. Legislative history from the 
1970 and 1990 Congresses cannot be “an authoritative 
interpretation of what the [1967] statute meant,” be- 
cause it is “the function of the courts and not the 
Legislature, much less a Committee of one House of the 
Legislature, to say what an enacted statute means.” 
Pierce v. Underwood, 487 U.S. 552, 566 (1988). 

Under Chevron, we defer to an agency’s interpreta- 
tion of a statute if “the statute is silent or ambiguous 
with respect to the specific issue” and “the agency’s 
answer is based on a permissible construction of the 
statute.” 467 U.S. at 843. We find no such ambiguity in 
this case. Further, EPA’s interpretation fails even the 
reasonableness standard of Chevron’s second part: it 
seems bizarre that a statute intended to improve 
human health would, as EPA claimed at argument, lock 
the agency into looking at only one half of a substance’s 
health effects in determining the maximum level for 
that substance. At oral argument even EPA counsel 
seemed reluctant to claim that the statute justified 
disregard of the beneficent effects of a pollutant bear- 
ing directly on the health symptoms that accounted for 
its being thought a pollutant at all (suppose, for exam- 
ple, a chemical that both impedes and enhances breath- 
ing, depending on the person or circumstances); he also 
seemed unable to distinguish that case from the one 
here—where the chemical evidently impedes breathing 
but provides defense against various cancers. 

Legally, then, EPA must consider positive identifi- 
able effects of a pollutant’s presence in the ambient air 
in formulating air quality criteria under § 108 and 
NAAQS under § 109. EPA’s other arguments are 

48a 

technical, and are of two sorts: those that allegedly 
show petitioners’ studies to be fatally flawed and those 
that allegedly show specific inflation of results in these 
studies. We need only consider the first sort, for EPA 
chose to give the studies no weight at all. 

Petitioners rely primarily on studies by Lutter and 
Cupitt. EPA found that these could be ignored because 
the marginal benefits are difficult, if not impossible, to 
quantify reliably and because there is “no convincing 
basis for concluding that any such effects . . . would 
be significant.” But these are not the criteria by which 
EPA assesses adverse health effects. It does not rigor- 
ously or uniformly demand either quantifiability, see, 

e.g., Ozone Final Rule, 62 Fed. Reg. at 38,860/3 (admit- 
ting that “quantitative risk estimates could not be 
developed” for certain adverse effects of ozone on which 
EPA regulated); EPA Ozone Brief at 48 (defending con- 
sideration of various effects that “played an important 
role in the Administrator’s final decision” despite ab- 
sence of quantification: “EPA did not estimate the risk 
for such effects because ‘information [was] too limited 
to develop quantitative estimates,’—not because there 
is doubt the effects occur.”) (alteration and emphasis in 
original) (citation omitted), or any specific level of 
significance. As we can see no reason for imposing a 
higher information threshold for beneficent effects than 
for maleficent ones, we have no basis for affirming 
EPA’s decision to disregard the studies. 

As we said above, we are remanding to EPA to for- 
mulate adequate decision criteria for its ordinary object 
of analysis—ill effects. We leave it to the agency on 
remand to determine whether, using the same approach 
as it does for those, tropospheric ozone has a beneficent 

49a 

effect, and if so, then to assess ozone’s net adverse 
health effect by whatever criteria it adopts. 

IV. Particulate Matter 

A. PM10 as Coarse Particle Indicator 

We now turn to petitioners’ challenges to the 
Agency’s regulation of coarse particulate pollution. 
Both the 1987 NAAQS and the proposed standards 
regulate all particles with diameters under 10 microme- 
ters, signified by the indicator PM10. The PM10 spec- 
trum includes both coarse and fine particles. While the 
main distinction between coarse and fine particles is the 
process by which they are produced, EPA and epidemi- 
ologists who study the health effects of particulate pol- 
lution identify coarse and fine particles through rough 
approximations of those particles’ diameters. Coarse 
particles, which become airborne usually from the 
crushing and grinding of solids, generally have diame- 
ters between 2.5 and 10 micrometers and can thus be 
identified by the indicator PM10-2.5. Fine particles, in- 
dicated in these new NAAQS by PM2.5, come mainly 
from combustion or gases and generally have diameters 
of 2.5 micrometers or less. 

Despite EPA’s conclusion that coarse and fine parti- 
cles pose independent and distinct threats to public 
health, the Agency chose not to adopt an indicator, such 
as PM10-2.5, that would measure only the coarse fraction 
of PM10. Petitioners make two arguments: that there is 
no scientific basis for regulating coarse particles at all, 
and that even if there were, retention of the PM10 
indicator simultaneously with the establishment of the 
new fine particle indicator is unsupported by evidence 

50a 

in the record and arbitrary and capricious. We agree 
with this latter argument. 

Beginning with petitioners’ first challenge, we think 
the record contains sufficient evidence to justify the 
Agency’s decision to regulate coarse particulate pollu- 
tion. While the relationship between PM10 pollution and 
adverse health effects justifying the 1987 NAAQS was 
well-established, see NRDC v. EPA, 902 F.2d 962, 967- 
68 (D.C. Cir. 1990), two studies contained in the record 
of these proceedings concentrated specifically on the 
health effects caused by the coarse fraction of PM10 
pollution. See Mary Ellen Gordian et al., “Particulate 
Air Pollution and Respiratory Disease in Anchorage, 
Alaska,” 104 Envtl. Health Persp. 290 (1996) (studying 
volcanic ash); Brockton J. Hefflin et al., “Surveillance 
for Dust Storms and Respiratory Diseases in Washing- 
ton State, 1991,” 49 Archives of Envtl. Health 170 
(1994) (studying fugitive dust). In addition, the record 
contains at least nine multivariate analyses finding 
statistically significant relationships with health effects 
for both PM2.5 and PM10, suggesting that the portion of 
PM10 pollution unaccounted for by PM2.5 (i.e., coarse 
particles) explains some of the observed adverse health 
effects. In other words, because regression analysis 
holds the PM2.5 component constant, the PM10 effect 
recognized in these equations actually evidences results 
from coarse particulate pollution. To be sure, peti- 
tioners have pointed to some evidence to the contrary. 
But given that our review is limited to “ascertaining 
that the choices made by the Administrator were rea- 
sonable and supported by the record,” and does not in- 
clude “judg[ing] the merits of competing expert views,” 
Lead Industries, 647 F.2d at 1160, we find ample sup- 

51a 

port for EPA’s decision to regulate coarse particulate 
pollution above the 1987 levels. 

Having found independent health consequences from 
coarse particulate pollution, EPA nevertheless decided 
to regulate the coarse fraction of PM10 indirectly, using 
PM10 (which includes both coarse and fine PM) as a 
“surrogate for coarse fraction particles.” PM Final 
Rule, 62 Fed. Reg. at 38,668/2. While recognizing that 
PM10-2.5 would have served as a satisfactory coarse 
particle indicator, EPA offers three justifications for its 
decision to use PM10 instead: (1) Both the Gordian and 
Hefflin studies used PM10, not PM10-2.5, as the variable in 
their models, (2) the PM10 standards will work in 
conjunction with the PM2.5 standards by regulating the 
portion of particulate pollution not regulated by the 
PM2.5 standards, and (3) a nationwide monitoring pro- 
gram for PM10 already exists. We find none of these 
explanations persuasive. 

As to the first argument, while acknowledging that 
the indicator used in the studies captures both coarse 
and fine particles, EPA nevertheless maintains that 
PM10 is an effective indicator for the regulation of 
coarse particulate pollution. “Adopting the indicator 
used in the studies,” the Agency says, “increases the 
likelihood that the level selected will result in the 
health protections predicted.” But as EPA’s own staff 
paper suggests, PM10 is “inherently confounded” by the 
presence of PM2.5 particles, meaning that any regulation 
of PM10 pollution will include both coarse and fine 
particles. See PM Staff Paper at V-59. Using PM10 as 
the coarse particle indicator, instead of PM10-2.5, will 
thus regulate more than just the coarse fraction of 
PM10, and the amount of coarse particulate pollution 

52a 

permitted will depend (quite arbitrarily) on the amount 
of PM2.5 pollution in the air. For example, assuming the 
50 microgram annual PM10 level adopted by the Agency 
and a region with an annual PM2.5 pollution level of 15 
micrograms, the PM10 indicator would prohibit coarse 
particulate (PM10-2.5) pollution from exceeding 35 micro- 
grams. But in an area with only 5 micrograms of PM2.5 
pollution, the NAAQS would permit coarse particulate 
pollution to reach as high as 45 micrograms. 

EPA’s second argument—that the PM10 standard will 
work in conjunction with the PM2.5 standard—suffers 
from the same deficiency. Accepting EPA’s finding of 
“profound physicochemical differences” between coarse 
and fine PM, PM Staff Paper at V-59, such that each 
requires independent regulation, we cannot discern 
exactly how a PM10 standard, instead of a PM10-2.5 stan- 
dard, will work alongside a PM2.5 standard to regulate 
only the coarse fraction of PM10. EPA provides no 
explanation to aid us in understanding its decision. In 
fact, as the example above indicates, it is the very pre- 
sence of a separate PM2.5 standard that makes retention 
of the PM10 indicator arbitrary and capricious. Far 
from working in conjunction to regulate coarse parti- 
cles, PM10 and PM2.5 indicators, when used together, 
lead to “double regulation” of the PM2.5 component of 
PM10 and potential underregulation of the PM10-2.5 com- 
ponent since the amount of PM10-2.5 permitted will 
always depend on the amount of PM2.5 in the air. 

EPA’s final argument is pragmatic. It maintains that 
PM10 is a better indicator than PM10-2.5 for coarse par- 
ticulate pollution because a nationwide monitoring 
program for PM10 already exists. But as EPA acknowl- 
edges elsewhere in its brief, NRDC bars EPA from 

53a 

considering factors unrelated to public health in setting 
air quality standards. Echoing our decision in Vinyl 
Chloride, NRDC held that “the Administrator may not 
consider cost and technological feasibility in determin- 
ing what is ‘safe’; such a determination ‘must be based 
solely upon the risk to health.’ ” NRDC, 902 F.2d at 973 
(quoting Vinyl Chloride, 824 F.2d 1146, 1166 (D.C. Cir. 
1990) (in banc)); see also American Petroleum Inst. v. 
Costle, 665 F.2d 1176, 1185 (D.C. Cir. 1981); Lead 
Industries, 647 F.2d at 1148-55. The administrative 
convenience of using PM10 cannot justify choosing an 
indicator poorly matched to the relevant pollution 
agent. 

In view of our conclusion that PM10 amounts to an 
arbitrary indicator for coarse particle pollution, we 
need not address petitioners’ separate challenge to the 
PM10 levels or secondary standards. We note, however, 
that whatever levels the Agency ultimately selects for 
coarse particle pollution will need to comply with the 
requirements set forth in Part I of this opinion. 

B. Fine Particles as “New Pollutant” 

The Attorneys General of Ohio, Michigan, and West 
Virginia (“state petitioners”) argue that EPA is regu- 
lating PM2.5 for the first time. Because they consider 
PM2.5 to be a “new pollutant,” they argue that § 108 of 
the Clean Air Act requires EPA to conduct further 
research on PM2.5’s health effects before listing it as a 
pollutant, to issue an air quality criteria document 
reflecting the latest science on the health effects of the 
pollutant, and to assist states by developing “data 
relating to the cost of installation and operation, energy 
requirements, emission reduction benefits, and environ- 

54a 

mental impact of the emission control technology.” 
42 U.S.C. § 7408(b)(1). 

Although EPA never responds to this argument, five 
northeastern states (as respondent intervenors and 
amici) do. Pointing out that previous NAAQS have 
always included PM2.5, these attorneys general support 
the EPA’s decision not to list PM2.5 separately as a new 
pollutant. We agree. 

The state petitioners cannot escape the fact that the 
original standards for particulate pollution using Total 
Suspended Particulates (TSP) as indicator, as well as 
the 1987 NAAQS that used PM10, included by definition 
every particle 2.5 micrometers and smaller. Moreover, 
in some areas fine particles often dominate PM10 pollu- 
tion. See PM Staff Paper at V-63. By refining the 
NAAQS to focus on smaller particles that EPA found 
posed distinct threats to public health, EPA has done 
with these regulations exactly what we held it could do 
in 1987 when it made the change from Total Suspended 
Particulates to PM10. See NRDC, 902 F.2d at 965-66. 
EPA’s decision to update the NAAQS to focus on PM2.5 
merely continues a trend based on evolving science. It 
does not violate the provisions of § 108 of the Clean Air 
Act. 

C. Failure to Identify a Biological Mechanism for 

Particulate Pollution’s Relationship to Adverse 
Health Effects 

Also challenging the establishment of a fine particle 
standard, non-state petitioners argue that EPA failed 
to explain the biological mechanism through which par- 
ticulate pollution causes adverse health effects. Even if 
epidemiological studies show robust statistical relation- 

55a 

ships between pollution and health effects, they say, the 
absence of proof of causation—i.e., how particles actu- 
ally interact with cells and organs to cause sickness and 
death—is fatal to the standard. We disagree. 

To begin with, the statute itself requires no such 
proof. The Administrator may regulate air pollutants 
“emissions of which, in his judgment, cause or contri- 
bute to air pollution which may reasonably be antici- 
pated to endanger public health or welfare.” 42 U.S.C. 
§ 7408(a)(1)(A) (1994) (emphasis added). Moreover, this 
court has never required the type of explanation peti- 
tioners seek from EPA. In fact, we have expressly held 
that EPA’s decision to adopt and set air quality stan- 
dards need only be based on “reasonable extrapolations 
from some reliable evidence.” NRDC v. Thomas, 805 
F.2d 410, 432 (D.C. Cir. 1986). Indeed, were we to 
accept petitioners’ view, EPA (or any agency for that 
matter) would be powerless to act whenever it first 
recognizes clear trends of mortality or morbidity in 
areas dominated by a particular pathogen. 

The numerous epidemiological studies appearing in 
this record, some of which EPA also used to support 
the 1987 NAAQS, easily satisfy the standard articu- 
lated in the statute and emphasized repeatedly in 
decisions of this court. Covering diverse geographic 
locations with widely varying mixes of air pollution, the 
studies found statistically significant relationships 
between air-borne particulates signified by a variety of 
indicators and adverse health effects. Given EPA’s 
statutory mandate to establish standards based on “the 
latest scientific knowledge,” 42 U.S.C. §§ 7408(a)(2), 
7409(d), the growing empirical evidence demonstrating 
a relationship between fine particle pollution and 

56a 

adverse health effects amply justifies establishment of 
new fine particle standards. 

D. Visibility Effects 

The Environmental Petitioners challenge the EPA’s 
decision to set the secondary PM2.5 NAAQS at levels 
equivalent to the primary NAAQS. According to the 
petitioners, the EPA’s failure to set the secondary 
NAAQS at more stringent levels will result in “adverse 
visibility impacts” in parts of the country. In view of 
our conclusion in Part I, above, that the EPA has not 
adequately explained the principles upon which it relied 
in setting the levels in the NAAQS for PM, we need not 
reach the main thrust of the petitioners’ challenge to 
the secondary NAAQS. On the other hand, the 
Environmental Petitioners have also raised a question 
of statutory interpretation, the resolution of which 
should assist the EPA if it revisits its decision to set the 
secondary PM2.5 NAAQS. 

In the PM Final Rule, the EPA decided “to address 
the welfare effects of PM on visibility by setting 
secondary standards identical to the suite of PM2.5 pri- 
mary standards, in conjunction with the establishment 
of a regional haze program under § 169A of the Act.” 
PM Final Rule, 62 Fed. Reg. at 38,679/3. Section 169A 
“declares as a national goal the prevention . . . and 
the remedying of any . . . impairment of visibility in 
mandatory class I Federal areas . . . result[ing] from 
manmade air pollution.” 42 U.S.C. § 7491. Mandatory 
class I areas include all international parks, and na- 
tional parks and wilderness areas of a certain size. See 
42 U.S.C. § 7472(a). The EPA concluded that reduction 
of PM2.5 levels in class I areas would benefit the sur- 
rounding areas as well because “the same haze that 

57a 

degrades visibility within or looking out from a national 
park also degrades visibility outside it.” PM Final 
Rule, 62 Fed. Reg. at 38,682/1. 

The Environmental Petitioners argue that § 
109(b)(2), 42 U.S.C. § 7409(b)(2), requires the EPA to 
set secondary NAAQS at a level sufficient to eliminate 
all adverse visibility effects and that it leaves the EPA 
no discretion to decide that some visibility impairment 
is better remedied through another program. This 
argument must be wrong. For, as the EPA argues, the 
Congress required the EPA to implement a regional 
haze program specifically in order to address adverse 
visibility effects that persist in class I areas after 
attainment of the secondary NAAQS. See 42 U.S.C. 
§ 7470(1) (purpose of this part of Clean Air Act is “to 
protect public . . . welfare from any actual or potential 
adverse effect which . . . may reasonably be antici- 
pate[d] to occur . . . notwithstanding attainment and 
maintenance of all [NAAQS]”). Accordingly, we con- 
clude that the Congress did not intend the secondary 
NAAQS to eliminate all adverse visibility effects and, 
therefore, that the EPA acted within the scope of its 
authority in deciding to rely upon the regional haze 
program to mitigate some of the adverse visibility 
effects caused by PM2.5. 

Conclusion 

We remand the cases to EPA for further con- 
sideration of all standards at issue. We do not vacate 
the new ozone standards because the standard is un- 
likely to engender costly compliance activities in light of 
our determination that it cannot be enforced by virtue 
of Clean Air Act § 181(a), 42 U.S.C. § 7511(a). We 
vacate the challenged coarse particulate matter stan- 

58a 

dards because EPA will have to develop different 
standards when it corrects the arbitrarily chosen PM10 
indicator. As to the fine particulate matter standards, 
we invite briefing on the question of remedy: possibili- 
ties include but are not limited to vacatur, non-vacatur 
subject to application to vacate, and non-vacatur.8 An 
order giving the briefing particulars will follow. 

Because of the substantial investment of time this 
matter has required and the many unresolved issues 
bearing on application of whatever standards may 
emerge, this panel will in the interest of judicial 
economy retain jurisdiction over the cases following 
remand. See Sierra Club v. Gorsuch, 715 F.2d 653, 661 
(D.C. Cir. 1983). 

8 Briefing should address the possibility that the previous 
particulate matter standard will spring back to life in response to 
our decision to vacate the new coarse particulate matter standard. 

59a 

TATEL, Circuit Judge, dissenting from Part I: 

The Clean Air Act has been on the books for decades, 
has been amended by Congress numerous times, and 
has been the subject of regular congressional oversight 
hearings. The Act has been parsed by this circuit no 
fewer than ten times in published opinions delineating 
EPA authority in the NAAQS-setting process. Yet this 
court now threatens to strike down section 109 of the 
Act as an unconstitutional delegation of congressional 
authority unless EPA can articulate an intelligible 
principle cabining its discretion. In doing so, the court 
ignores the last half-century of Supreme Court non- 
delegation jurisprudence, apparently viewing these 
permissive precedents as mere exceptions to the rule 
laid down 64 years ago in A.L.A. Schechter Poultry 
Corp. v. United States, 295 U.S. 495 (1935). Because 
section 109’s delegation of authority is narrower and 
more principled than delegations the Supreme Court 
and this court have upheld since Schechter Poultry, and 
because the record in this case demonstrates that 
EPA’s discretion was in fact cabined by section 109, I 
respectfully dissent. 

Section 109 requires EPA to publish 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.” 42 U.S.C. § 
7409(b)(1) (1994). Compare section 109 to the language 
of section 303 of the Communications Act of 1934, which 
gave the FCC authority to regulate broadcast licensing 
in the “public interest,” and which the Supreme Court 
sustained in National Broadcasting Co. v. United 
States, 319 U.S. 190, 225-26 (1943). The FCC’s general 

60a 

authority to issue regulations “as public convenience, 
interest, or necessity requires” was sustained in United 
States v. Southwestern Cable Co., 392 U.S. 157, 178 
(1968). The Supreme Court has sustained equally broad 
delegations to other agencies, including the Price 
Administrator’s authority to fix “fair and equitable” 
commodities prices, Yakus v. United States, 321 U.S. 
414, 426-27 (1944), the Federal Power Commission’s 
authority to determine “just and reasonable” rates, 
FPC v. Hope Natural Gas Co., 320 U.S. 591, 600 (1944), 
the War Department’s authority to recover “excessive 
profits” earned on military contracts, Lichter v. United 
States, 334 U.S. 742, 778-786 (1948), and the Attorney 
General’s authority to regulate new drugs that pose an 
“imminent hazard to public safety,” Touby v. United 
States, 500 U.S. 160, 165 (1991). See also Milk Indus. 
Foundation v. Glickman, 132 F.3d 1467, 1475 (D.C. Cir. 
1998) (upholding delegation to Secretary of Agriculture 
to approve interstate compacts upon a finding of “com- 
pelling public interest”). 

Given this extensive Supreme Court precedent sus- 
taining general congressional delegations, no wonder 
the First Circuit rejected a similar nondelegation chal- 
lenge to the Clean Air Act’s “requisite to protect the 
public health” language: 

The power granted to EPA is not “unconfined and 
vagrant”. [Schechter Poultry, 295 U.S. at 551 (Car- 
dozo, J., concurring).] The Agency has been given a 
well defined task by Congress—to reduce pollution 
to levels “requisite to protect the public health”, in 
the case of primary standards. The Clean Air Act 
outlines the approach to be followed by the Agency 
and describes in detail many of its powers. . . . Yet 

61a 

there are many benchmarks to guide the Agency 
and the courts in determining whether or not EPA 
is exceeding its powers, not the least of which is that 
the rationality of the means can be tested against 
goals capable of fairly precise definition in the 
language of science. 

Administrative agencies are created by Congress 
because it is impossible for the Legislature to 
acquire sufficient information to manage each detail 
in the long process of extirpating the abuses identi- 
fied by the legislation; the Agency must have 
flexibility to implement the congressional mandate. 
Therefore, although the delegation to EPA was a 
broad one, . . . we have little difficulty concluding 
that the delegation was not excessive. 

South Terminal Corp. v. EPA, 504 F.2d 646, 677 (1st 
Cir. 1974). 

I do not agree with my colleagues that International 
Union, UAW v. OSHA, 938 F.2d 1310 (D.C. Cir. 1991) 
(“Lockout/Tagout I”), requires a different result. That 
case remanded to OSHA for a more precise definition of 
section 3(8) of the Occupational Safety and Health Act, 
which granted the Agency authority to enact workplace 
safety standards “reasonably necessary or appropriate 
to provide safe or healthful employment or places of 
employment.” Id. at 1316. The Clean Air Act does not 
delegate to EPA authority to do whatever is “reason- 
ably necessary or appropriate” to protect public health. 
Instead, the statute directs the Agency to fashion 
standards that are “requisite” to protect the public 
health. In other words, EPA must set pollution stan- 
dards at levels necessary to protect the public health, 

62a 

whether “reasonable” or not, whether “appropriate” or 
not. 

Moreover, in setting standards “requisite to protect 
the public health” EPA discretion is not unlimited. The 
Clean Air Act directs EPA to base standards on “air 
quality criteria” that “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 quanti- 
ties.” 42 U.S.C. § 7408(a)(2); see id. § 7409(b)(1); see 
also id. § 7408(a)(2) (requiring air quality criteria, “to 
the extent practicable,” to “include information on—(A) 
those variable factors (including atmospheric condi- 
tions) which of themselves or in combination with other 
factors may alter the effects on public health or welfare 
of such air pollutant; (B) the types of air pollutants 
which, when present in the atmosphere, may interact 
with such pollutant to produce an adverse effect on 
public health or welfare; and (C) any known or antici- 
pated adverse effects on welfare”). Indeed, the princi- 
ples constraining EPA discretion are at least as specific 
as those this court sustained in Lockout/Tagout II, i.e., 
that OSHA must identify a “ ‘significant’ safety risk, to 
enact a safety standard that provides ‘a high degree of 
worker protection’.” International Union, UAW v. 
OSHA, 37 F.3d 665, 669 (D.C. Cir. 1994) (“Lockout/ 
Tagout II”). By directing EPA to set NAAQS at levels 
“requisite”—not reasonably requisite—to protect the 
public health with “an adequate margin of safety,” the 
Clean Air Act tells EPA exactly the same thing, i.e., 
ensure a high degree of protection. 

63a 

Although this court’s opinion might lead one to think 
that section 109’s language permitted EPA to exercise 
unfettered discretion in choosing NAAQS, the record 
shows that EPA actually adhered to a disciplined 
decisionmaking process constrained by the statute’s 
directive to set standards “requisite to protect the 
public health” based on criteria reflecting the “latest 
scientific knowledge.” To identify which health effects 
were “significant enough” to warrant protection, EPA 
followed guidelines published by the American Thoracic 
Society. See National Ambient Air Quality Standards 
for Ozone: Proposed Decision, 61 Fed. Reg. 65,716, 
65,722/1 (1996). It then set the ozone and fine particle 
standards within ranges recommended by CASAC, the 
independent scientific advisory committee created 
pursuant to section 109 of the Act. See 42 U.S.C. § 
7409(d)(2). 

CASAC must consist of at least one member of the 
Nation- al Academy of Sciences, one physician, and one 
person representing state air pollution control agencies. 
See id. § 7409(d)(2)(A). In this case, CASAC also in- 
cluded medical doctors, epidemiologists, toxicologists 
and environmental scientists from leading research 
universities and institutions throughout the country. 
EPA must explain any departures from CASAC’s re- 
commendations. See id. § 7607(d)(3). Bringing scien- 
tific methods to their evaluation of the Agency’s 
Criteria Document and Staff Paper, CASAC provides 
an objective justification for the pollution standards the 
Agency selects. Cf. Daubert v. Merrell Dow Pharma- 
ceuticals, Inc., 509 U.S. 579, 593 (1993) (“‘Scientific 
methodology today is based on generating hypotheses 
and testing them to see if they can be falsified; indeed, 
this methodology today is what distinguishes science 

64a 

from other fields of human inquiry.’”) (citation omitted). 
Other federal agencies with rulemaking responsibilities 
in technical fields also rely heavily on the recommenda- 
tions, policy advice, and critical review that scientific 
advisory committees provide. See, e.g., 21 U.S.C. § 
355(n) (describing scientific advisory panels for the 
Food and Drug Administration); 49 U.S.C. § 44912(c) 
(creating a scientific advisory panel for the Federal 
Aviation Administration). 

Beginning with CASAC’s ozone recommendations— 
not one member recommended going below .08 ppm— 
EPA gave two perfectly rational explanations for the 
level it selected. First, it set the annual level based on 
the different types of health effects observed above and 
below .08 ppm. Particularly below .08, the Agency de- 
termined, “[t]he most certain [ozone-]related effects, 
while judged to be adverse, are transient and reversi- 
ble.” National Ambient Air Quality Standards for 
Ozone, 62 Fed. Reg. 38,856, 38,868/2 (1997) (emphasis 
added). Characterizing this explanation as saying 
nothing more than that “lower exposure levels are as- 
sociated with lower risk to public health,” Maj. Op. at 
10, my colleagues find the Agency’s reasoning unintelli- 
gible. But EPA did not find simply that public health 
risks decrease at lower levels. Instead, it found that 
public health effects differ below .08 ppm, i.e., that they 
are “transient and reversible.” 

Second, EPA explained that the level should not be 
set below naturally occurring background ozone con- 
centrations. The Agency selected .08 ppm because it 
found that “a 0.07 ppm level would be closer to peak 
background levels that infrequently occur in some areas 
due to nonanthropogenic sources of [ozone] precursors, 

65a 

and thus more likely to be inappropriately targeted in 
some areas on such sources.” 62 Fed. Reg. at 38,868/3. 
Of course, any level of ozone pollution above back- 
ground concentrations is closer to background levels 
than one just above it. See Maj. Op. at 11. But as I read 
EPA’s explanation, the Agency found that peak 
background levels sometimes occur at .07 ppm, not at 

.08 ppm. Indeed, the data EPA provided in its “Re- 
sponses to Significant Comments” show a range of 
background concentrations from a low of .042 ppm in 
Olympic National Park in Washington to a high of .075 
ppm in Quachita National Forest in Arizona. No region 
registered background levels above .075 ppm. See U.S. 

ENVIRONMENTAL PROTECTION AGENCY, RE- 
SPONSES TO SIGNIFICANT COMMENTS ON THE 1996 
PROPOSED RULE ON THE NATIONAL AMBIENT 
AIR QUALITY STANDARDS FOR OZONE 94-96 (July 
1997). In other words, by setting the annual standard 
at .08 rather than .07 ppm, EPA ensured that if a region 
surpasses the ozone standard, it will do so because of 
controllable human activity, not because of uncontrolla- 
ble natural levels of ozone. 

EPA offered an equally reasonable explanation for 
the fine particle pollution standard. Again limiting 
itself to the range approved by CASAC, EPA set the 
annual standard for PM2.5 pollution at the lowest level 
where it had confidence that the epidemiological evi- 
dence (filtered through peer-reviewed, published stud- 
ies) displayed a statistically significant relationship 
between air pollution and adverse public health effects. 

Recognizing that its decision must “accurately reflect 
the latest scientific knowledge useful in indicating the 
kind and extent of all identifiable effects on public 

66a 

health,” 42 U.S.C. § 7408(a)(2), EPA focused on three 
studies in the record that displayed a statistically 
significant relationship between fine particle pollution 
and adverse health effects: Joel Schwartz et al., Is 
Daily Mortality Associated Specifically with Fine 
Particles?, 46 J. AIR & WASTE MGMT. ASS’N 927 
(1996); Joel Schwartz et al., Acute Effects of Summer 
Air Pollution on Respiratory Symptom Reporting in 
Children, 150 AM. J. RESPIRATORY & CRITICAL 
CARE MED. 1234 (1994); and Douglas W. Dockery et 
al., An Association between Air Pollution and Mortal- 
ity in Six U.S. Cities, 329 NEW ENG. J. MED. 1753 
(1993). The Agency explained that “there is generally 
greatest statistical confidence in observed associations 
[between fine particle pollution and adverse health 
effects] for levels at and above the mean concentration 
[of pollution observed in the studies that showed a 
statistically significant relationship].” National Ambi- 
ent Air Quality Standards for Particulate Matter, 62 
Fed. Reg. 38,652, 38,676/1 n.42 (1997) (emphasis added). 
Allowing “an adequate margin of safety,” EPA then set 
the annual fine particle standard just below the lowest 
mean pollution levels observed in those studies, at 15 
•g/m3. See id. at 38,676/1 (“An examination of the long- 
term means from the combined six city analyses of daily 
mortality [Schwartz et al. (1996)] and morbidity 
[Schwartz et al. (1994)], together with those from 
studies in individual cities for which statistically 
significant PM-effects associations are reported . . . 
finds mean concentrations ranging from about 16 to 
about 21 •g/m3. . . .”); id. at 38,676/2 (“[The EPA] Staff 

Paper assessment of the concentration-response results 
[from Dockery et al. (1993)], concluded that the evi- 
dence for increased risk was more apparent at annual 
concentrations at or above 15 •g/m3. . . .”). 

67a 

In a passage directly answering this court’s concerns, 
see Maj. Op. at 11-12, the Staff Paper explained why the 
long-term mean served as a reasonable level for setting 
the fine particle NAAQS: 

The mean (or median) concentration may serve as a 
reasonable cutpoint of increased PM health risk 
since at this point there is generally the greatest 
confidence (i.e., the smallest confidence intervals) in 
the association and the reported [relative risk] 
estimates. The mean concentration considered by 
staff as most informative to test implications of 
potential alternative concentration-response func- 
tions is the minimum mean concentration associ- 
ated with a study or studies reporting statistically 
significant increases in risk across a number of 
study locations. . . . 

OFFICE OF AIR QUALITY PLANNING AND 
STANDARDS, U.S. ENVIRONMENTAL PROTECTION 
AGENCY, REVIEW OF NATIONAL AMBIENT AIR 
QUALITY STANDARDS FOR PARTICULATE MAT- 
TER: POLICY ASSESSMENT OF SCIENTIFIC AND 
TECHNICAL INFORMATION, at E-4 (1996) (emphasis 
added). 

EPA thus did not, as my colleagues charge, arbitrar- 
ily pick points on the ozone and particulate pollution 
continua indistinguishable from any other. Instead, 
acting pursuant to section 109’s direction that it estab- 
lish standards that, based on the “latest scientific 
knowledge” are “requisite” to protect the public health 
with “an adequate margin of safety,” and operating 
within ranges approved by CASAC, the Agency set the 
ozone level just above peak background concentrations 
where the most certain health effects are not transient 

68a 

and reversible, and the fine particle level at the lowest 
long-term mean concentration observed in studies that 
showed a statistically significant relationship between 
fine particle pollution and adverse health effects. 
Whether EPA arbitrarily selected the studies it relied 
upon or drew mistaken conclusions from those studies 
(as petitioners argue), or whether EPA failed to live up 
to the principles it established for itself (as my col- 
leagues believe, see Maj. Op. at 9-12), has nothing to do 
with our inquiry under the nondelegation doctrine. 
Those issues relate to whether the NAAQS are arbi- 
trary and capricious. See NRDC v. EPA, 902 F.2d 962, 
969, 971 (D.C. Cir. 1989). The Constitution requires 
that Congress articulate intelligible principles; Con- 
gress has done so here. 

A final point. Unlike OSHA, which Lockout/Tagout I 
recognized has authority to reach into every workplace 
to dictate what is safe, to impose extensive civil and 
criminal penalties, and “to decide which firms will live 
and which will die,” Lockout/Tagout I, 938 F.2d at 1318, 
EPA regulates primarily by setting standards for 
states to develop their own plans. See 42 U.S.C. § 
7401(a)(3) (Congress finds “that air pollution prevention 

. . . and air pollution control at its source is the 
primary responsibility of States and local govern- 
ments.”). Indeed, because states have three years to 
submit implementation plans, which are themselves 
subject to notice, comment, public hearing, and fre- 
quent renegotiation, we will not know for years pre- 
cisely how the ozone and particle NAAQS will actually 
affect individual businesses. Only if a state fails to 
produce an acceptable plan can EPA terminate federal 
highway funds or impose its own implementation plan. 
Because the Clean Air Act gives politically accountable 

69a 

state governments primary responsibility for deter- 
mining how to distribute the burdens of pollution 
reduction and therefore how the NAAQS will affect 
specific industries and individual businesses, courts 
have less reason to second-guess the specificity of the 
congressional delegation. Moreover, if the states 
disagree with the standards EPA has set, they have 
535 representatives in Congress to turn to for help. In 
fact, legislation to overturn the very NAAQS at issue in 
this case was introduced in the last Congress. See H.R. 
1984, 105th Cong. (1997) (“A bill to provide for a four- 
year moratorium on the establishment of new stan- 
dards for ozone and fine particulate matter under the 
Clean Air Act, pending further implementation of the 
Clean Air Act Amendments of 1990, additional review 
and air quality monitoring under that Act.”); S. 1084, 
105th Cong. (1997) (“A bill to establish a research and 
monitoring program for the national ambient air quality 
standards for ozone and particulate matter and to 
reinstate the original standards under the Clean Air 
Act, and for other purposes.”). 

70a 

APPENDIX B 

UNITED STATES COURT OF APPEALS 
FOR THE DISTRICT OF COLUMBIA CIRCUIT 

No. 97-1440 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

Nos. 97-1440, 97-1546, 97-1548, 97-1551 to 97-1553, 
97-1555, 97-1559, 97-1561, 97-1562, 97-1565, 97-1567, 
97-1571, 97-1573, 97-1574, 97-1576, 97-1578, 97-1579, 
97-1582,97-1585 to 97-1588, 97-1592, 
97-1594, 97-1596 to 97-1598 

Nos. 97-1441, 97-1502, 97-1505, 97-1508 to 97-1510, 
97-1512 to 97-1514, 97-1518, 97-1519, 97-1526, 97-1531, 
97-1539, 97-1566, 97-1568, 97-1570, 97-1572, 97-1575, 
97-1584, 97-1589, 97-1591, 97-1595, 97-1619 

[Filed October 29, 1999] 

BEFORE: WILLIAMS, GINSBURG, AND TATEL, Cir- 
cuit Judges. 

Opinion PER CURIAM on petitions for rehearing. 

71a 

Opinion concurring in partial grant of rehearing and 
dissenting in part from the panel’s denial of rehearing 
filed by Circuit Judge TATEL. 

ORDER 

PER CURIAM 

This matter is before the court for consideration of 
respondent Environmental Protection Agency’s (EPA) 
petition for panel rehearing in Nos. 97-1440 and 97- 
1441, the responses thereto, and the petitions for panel 
rehearing of intervenors-respondents New Jersey and 
Massachusetts in Nos. 97-1440 and 97-1441, Citizen for 
Balanced Transportation, et al. in No. 97-1440, and the 
American Lung Association in Nos. 97-1440 and 97- 
1441. Upon consideration of the foregoing, it is 

ORDERED that the petitions of EPA, New Jersey 
and Massachusetts, and the American Lung Association 
be granted in part. The court accordingly modifies 
Parts III.A.2 & .3 and the conclusion of the court’s 
original opinion as set forth in the opinion of the court 
filed herein this date. It is 

FURTHER ORDERED that the remainder of EPA, 
New Jersey and Massachusetts, and the American 
Lung Association’s petitions be denied and that Citizen 
for Balanced Transportation’s petition be denied. 

72a 

Opinion for the Court filed PER CURIAM: 

The Environmental Protection Agency petitions for 
rehearing, challenging this court’s holdings that: (1) 
with respect to the factors the agency uses to deter- 
mine the degree of public health concern associated 
with different levels of a pollutant, it “appears to have 
articulated no ‘intelligible principle’ to channel its 
application of these factors; nor is one apparent from 
the statute,” American Trucking Ass’ns v. United 
States Environmental Protection Agency, 175 F.3d 
1027, 1034 (D.C. Cir. 1999); (2) “Subpart 2, not Subpart 
1, provides the classifications and attainment dates for 
any areas designated nonattainment under a revised 
primary ozone NAAQS, and the EPA must enforce any 
revised primary ozone NAAQS under Subpart 2,” id. at 
1050; and (3) “EPA must consider positive identifiable 
effects of a pollutant’s presence in the ambient air in 
formulating air quality criteria under § 108 and NAAQS 
under § 109,” id. at 1052. For the following reasons, we 
grant the petition for rehearing in part and deny it in 
part. 

I. Delegation 

In the EPA’s petition for rehearing, counsel for the 
agency argue that § 109 of the Clean Air Act contains 
the following principle limiting the agency’s discretion: 
“The levels [set in a NAAQS] must be necessary for 
public health protection: neither more nor less strin- 
gent than necessary, but ‘requisite.’ ” 

EPA Pet. at 8 
(emphases in original). Further, counsel claim that in 
setting the NAAQS at issue in this case the agency 

73a 

applied corollaries of this principle, one for particulate 
matter, one for ozone,9 to derive determinate standards. 

In denying the EPA’s petition for rehearing on this 
issue, we note that the agency previously put forward 
neither the assertedly intelligible principle its counsel 
now claim to find in the statute nor the corollaries its 
counsel now implicitly derive therefrom. To be sure, in 
the rulemakings that set the NAAQS, the EPA men- 
tioned the corollary propositions its counsel now claim 
served as intelligible limiting principles, but the agency 
did not identify either as a limit upon its discretion; the 
EPA never suggested that it could not (or in a later 
rulemaking would not) base a NAAQS upon evidence 
that did not meet the 95 percent confidence level or 
that revealed adverse but transient effects. 

10 In its 
briefs defending the NAAQS, the EPA merely asserted 
that the Clean Air Act provides an intelligible principle; 
it failed both to state that principle and to argue that its 
revised NAAQS were promulgated in accordance with 
that principle. EPA PM Brief at 145-49; EPA Ozone 
Brief at 77-80. Indeed, the EPA’s briefs in each of 
these two cases contained the same four sentences 

9 For particulate matter, counsel now state that the EPA’s 
decision was determined by the norm of “the 95 percent confidence 
level to separate results that could be the product of chance from 
more convincing evidence of causation.” EPA Pet. at 15. For 
ozone, counsel now state that EPA inferred the existence of effects 
below 0.08 ppm, but nonetheless concluded that they were “less 
serious because they are ‘transient and reversible.’ ” 
EPA Pet. at 

16. 

10 The court’s opinion mentioned EPA’s observation in the re- 
cord that effects of ozone concentrations below the standard se- 
lected were “transient and reversible,” 175 F.3d at 1035, but only 
in connection with the dissent’s suggestion, see id. at 1059, that 
this was the controlling principle. 

74a 

assuring the court that the statute provides a principle 
without explaining what the agency understands that 
principle to be: 

[Section] 109(b)(1) requires EPA to promulgate 
NAAQS based on air quality criteria issued under 
§ 108 that are “requisite to protect the public 
health” with “an adequate margin of safety.” This 
language and related legislative history provide 
directions for EPA to follow in setting the NAAQS. 
Moreover, EPA has consistently interpreted § 
109(b)(1) to provide further decisionmaking criteria 
to guide the standard setting process. Thus, the 
CAA provides a more than sufficient “intelligible 
principle” to guide EPA’s discretion. EPA Ozone 
Brief at 78; see also EPA PM Brief at 148. 

These sentences begged the key question about that 
intelligible principle: “What is it?” 

As we noted in our first opinion in this case, when 
“statutory language and an existing agency interpreta- 
tion involve an unconstitutional delegation of power, 
but an interpretation without the constitutional weak- 
ness is or may be available, our response is not to strike 
down the statute but to give the agency an opportunity 
to extract a determinate standard on its own.” 175 F.3d 
at 1038. Counsel for the EPA have now extracted from 
the statute what they contend is an intelligible principle 
limiting the EPA’s discretion. We express no opinion 
upon the sufficiency of that principle; only after the 
EPA itself has applied it in setting a NAAQS can we 
say whether the principle, in practice, fulfills the pur- 
poses of the nondelegation doctrine. See Yakus v. 
United States, 321 U.S. 414, 424-26 (1944); Amalga- 

75a 

mated Meat Cutters v. Connally, 337 F. Supp. 737, 759 
(D.D.C. 1971) (Leventhal, J., for three-judge panel). 

A final word about our nondelegation holding: The 
Supreme Court has long held that an ambiguous 
principle in a statute delegating power to an agency can 
gain “meaningful content from the purpose of the Act, 
its factual background and the statutory context in 
which [it] appear[s].” American Power & Light Co. v. 
SEC, 329 U.S. 90, 104 (1946); see also Federal Radio 
Comm’n v. Nelson Bros. Bond & Mort. Co, 289 U.S. 
266, 285 (1933) (upholding delegation to Federal Radio 
Commission to grant licenses “as public convenience, 
interest or necessity requires” in light of “its context 
[and] the nature of radio transmission and reception”; 
Fahey v. Mallonee, 332 U.S. 245, 250 (1947) (upholding 
delegation to the Federal Home Loan Bank Board to 
promulgate regulations for the appointment of a 
conservator for savings and loan associations in view of 
the banking industry’s “well-defined practices for the 
appointment of conservators”). This court has done the 
same. See, e.g., National Ass’n of Broadcasters v. 
Copyright Royalty Tribunal, 675 F.2d 367, 376 n.12 
(1982) (finding an intelligible principle to guide the 
tribunal in disbursing cable royalty fees in “specific 
statements in the legislative history and in the general 
philosophy of the Act itself ”); Amalgamated Meat 
Cutters, 337 F. Supp. at 747-49 (interpreting the Eco- 
nomic Stabilization Act of 1970 in light of “the historic 
context of government stabilization measures” in order 
to “negative[ ] a conclusion that the whole program was 
set adrift without a rudder”). To choose among per- 
missible interpretations of an ambiguous principle, of 
course, is to make a policy decision, and since Chevron 
it has been clear that “[t]he responsibilities for assess- 

76a 

ing the wisdom of such policy choices . . . are not 
judicial ones.” Chevron U.S.A. Inc. v. NRDC, 467 U.S. 
837, 866 (1984). Accordingly, just as we must defer to 
an agency’s reasonable interpretation of an ambiguous 
statutory term, we must defer to an agency’s reason- 
able interpretation of a statute containing only an am- 
biguous principle by which to guide its exercise of 
delegated authority. But see Kenneth Culp Davis, A 
New Approach to Delegation, 36 U. Chi. L. Rev. 713, 
713 (1969) (arguing that “judicial inquiries [under the 
nondelegation doctrine] should shift from statutory 
standards to administrative safeguards”). In sum, the 
approach of the Benzene case, in which the Supreme 
Court itself identified an intelligible principle in an 
ambiguous statute, has given way to the approach of 
Chevron. See Industrial Union Dep’t v. American 
Petroleum Inst. (Benzene), 448 U.S. 607, 642, 646 (1980) 
(Stevens, J., plurality) (interpreting § 3(8) of the Occu- 
pational Health and Safety Act to require “a threshold 
finding . . . that significant risks are present,” thereby 
finding in the statute an intelligible principle). 

11 

II. Subpart 2 and the Revised Ozone Standard 

In its petition for rehearing, the EPA challenges the 
holdings in Parts III.A.2 and III.A.3 of our original 
opinion, see 175 F.3d at 1048-51, as well as our juris- 

11 We note that Judge Silberman’s dissent from the denial of 
rehearing en banc turns largely on his dim view of the Court’s use 
of the non-delegation doctrine in Benzene, which he characterizes 
as “only a makeweight, tossed into the analysis . 

. . to help justify 

the result.” Whatever the merits of Judge Silberman’s critique of 
Benzene, we do not see how a lower court can properly rest its 
jurisprudence on the rejection of a Supreme Court decision. 

77a 

diction to reach those issues. We address the juris- 
dictional point first. 

A. Jurisdiction 

The EPA argues that because it has taken no final 
action implementing the revised NAAQS this court 
lacks jurisdiction to reach the question whether Sub- 
part 2 prevents the agency from implementing a 
revised ozone NAAQS under Subpart 1. See 42 U.S.C. 
§ 7607(b) (limiting this court’s jurisdiction to review of 
“nationally applicable regulations promulgated, or final 
agency action taken, by the Administrator”); see also 
Sierra Club v. Thomas, 828 F.2d 783, 792 (D.C. Cir. 
1987). 

12 That this claim is raised for the first time in a 
petition for rehearing does not, of course, alter our 
obligation to “satisfy [our]self . . . of [our] own juris- 
diction.” Steel Co. v. Citizens for a Better Environ- 
ment, 118 S. Ct. 1003, 1012-13 (1998). 

Whether agency action is final for purposes of 
§ 7607(b) entails a functional, not a formal, inquiry. See 
NRDC v. EPA, 22 F.3d 1125, 1132-33 (D.C. Cir. 1994); 
Ciba-Geigy Corp. v. EPA, 801 F.2d 430, 436 (D.C. Cir. 
1986) (“Once the agency publicly articulates an une- 
quivocal position . . . and expects regulated entities to 
alter their primary conduct to conform to that position, 
the agency has voluntarily relinquished the benefit of 
postponed judicial review”). In this case, “there is 
nothing tentative about the EPA’s interpretation of 

12 The EPA has yet to designate an area nonattainment. There- 
fore, although the agency does not so argue, if it were correct, then 
this court would also lack jurisdiction to decide, as it did, that 
Subpart 2 does not alter the agency’s power to designate areas as 
nonattainment under a revised NAAQS. See 175 F.3d at 1047-48. 

78a 

[Subpart 2]; it is unambiguous and devoid of any sug- 
gestion that it might be subject to subsequent revi- 
sion.” Her Majesty the Queen ex rel. Ontario v. EPA, 
912 F.2d 1525, 1532 (D.C. Cir. 1990); see also Final Rule: 
National Ambient Air Quality Standards for Ozone, 62 
Fed. Reg. 38,856, 38,885/2 (1997) (“There is no language 
in sections 181 or 182 that precludes the implementa- 
tion of a different [ozone] standard under other author- 
ity [i.e., Subpart 1]; those provisions [i.e., Subpart 2] 
simply govern the implementation of the 1-hour, 0.12 
ppm O3 standard”). Moreover, by promulgating a 
revised ozone NAAQS the EPA has triggered the pro- 
visions of §§ 107(d)(1) and 172, which impose a number 
of requirements upon the states, the first being that the 
Governor of each state must determine which areas do 
not presently comply with the revised NAAQS; those 
areas that do not comply will ultimately be required to 
do so. The EPA, therefore, has reached a final decision 
regarding its power to implement its revised ozone 
standard, which this court has jurisdiction to review. 

13 

13 The EPA attempts to buttress its jurisdictional argument by 
reference to 42 U.S.C. § 7502(a)(1)(B), which it claims “defers chal- 
lenges to EPA’s implementation decisions classifying areas for 
setting attainment dates until EPA takes final action on a SIP . . . 
or triggers sanctions . . . [after] a state fails to submit a SIP.” 
EPA Pet. at 19. The section to which the EPA refers states as 
follows: “The Administrator shall publish a notice in the Federal 
Register announcing each [attainment or nonattainment] classifica- 
tion. . . . Such classification . . . shall not be subject to judicial 

review until the Administrator takes final action under [the stat- 
utes the EPA cites in its petition].” That is, the EPA’s decision to 
classify a particular area as attainment or nonattainment is not 
subject to review merely because the EPA published that decision 
in the Federal Register. Neither this section nor the analogous 
§ 7511(a)(3), to which the EPA also cites, prevents a court from 

79a 

The EPA also argues that the statements in its 
preamble regarding implementation are not “ripe for 
review,” a point which it raised in a single sentence in 
its original brief to this court. EPA Pet. at 19; EPA 
Ozone Brief at 74. The question whether Subpart 2 
prevents the EPA from designating an area as non- 
attainment under its revised ozone standard or from 
implementing that designation except in conformity 
with Subpart 2 is a pure question of law, the resolution 
of which would not benefit from a more concrete 
setting. As the agency’s action is undoubtedly final, the 
question is fit for review. See Rio Grande Pipeline Co. 

v. FERC, 178 F.3d 533, 540-41 (D.C. Cir. 1999). 

B. Subpart 2 and the EPA’s Authority to Enforce a 

Revised Ozone Standard 

The EPA’s arguments in its petition for rehearing do 
not convince us that we erred in rejecting the EPA’s 
contention that “the reference to §107(d) in §181(a)(1) 
relates only to designations made under § 107(d)(4),” 
175 F.3d at 1050, and in holding instead that “§ 181(a) 
clearly encompasses nonattainment designations made 
under all subsections of § 107(d).” Id. Indeed, we note 
that the EPA has abandoned its original position, 
arguing now that the “most logical reading” of § 181(a) 
is that the reference to § 107(d) includes §§ 107(d)(1)(C) 
and 107(d)(4). EPA Pet. at 24. We find this new read- 
ing no more persuasive than the old. As the EPA 
notes, all five Subparts of the Clean Air Act providing 
requirements for nonattainment areas begin with a 
reference to § 107(d). See 42 U.S.C. §§ 7502(a)(1)(A), 
7511(a)(1), 7512(a)(1), 7513(a), 7514(a). It is by no 

deciding, prior to the classification of a particular area, whether 
the agency has validly promulgated a revised standard. 

80a 

means clear, however, that the references to § 107(d) in 
Subparts 1 and 3 through 5 include only designations 
made under §§ 107(d)(1)(C) and (d)(4). Not only does 
the EPA never argue that they are so limited, but on 
its theory the reference to § 107(d) in Subpart 1 also 
encompasses designations made under § 107(d)(1)(A). 
EPA Pet. at 25. Accordingly, we reject the EPA’s new 
interpretation of § 181(a), for it is contrary to “the nor- 
mal rule of statutory construction that identical words 
used in different parts of the same act are intended to 
have the same meaning.” Gustafson v. Alloyd Co., 513 
U.S. 561, 570 (1995). 

Still, the EPA does raise two points relating to 
Subpart 2 which lead us to grant the EPA’s petition for 
rehearing in part and to make the following revisions to 
our opinion. 

The EPA correctly points out that we erroneously 
treated the attainment dates in the table in Subpart 2 
as representing the Congress’s judgment about what is 
“as expeditiously as practicable” in reducing the level of 
ozone in an area; in fact, those dates represent what the 
Congress set as outer limits. See 42 U.S.C. § 7511(a)(1) 
(“For each area classified under this subsection, the 
primary standard attainment date for ozone shall be as 
expeditiously as practicable but not later than the date 
provided in table 1”). EPA Pet. at 25 n.35. Accord- 
ingly, we grant the EPA’s petition for rehearing to the 
extent of deleting the final three sentences of Part 

III.A.3, see 175 F.3d at 1051, and substituting for them 
the following sentence: 

Therefore, we conclude that Subpart 2 erects no bar 
to the EPA’s requiring compliance with a revised 

81a 

secondary ozone NAAQS “as expeditiously as 
practicable.” 

The EPA also contends that the conclusion to Part 

III.A.2, see id. at 1050 (“the EPA must enforce any 
revised primary ozone NAAQS under Subpart 2”), 
conflicts with our description of that same conclusion at 
the end of the opinion, see id. at 1057 (revised ozone 
NAAQS “cannot be enforced by virtue of [Subpart 2]”). 
We agree that the two sentences are in tension. To 
clarify the matter, we grant the EPA’s petition for 
rehearing to the extent of making the following two 
revisions to our original opinion. First, we replace the 
final paragraph of Part III.A.2, see id. at 1050, with the 
following: 

In sum, because the reference to §107(d) in § 
181(a)(1) includes the designation of an area as non- 
attainment for ozone under a revised ozone NAAQS, 
that is, under § 107(d)(1), the EPA can enforce a 
revised primary ozone NAAQS only in conformity 
with Subpart 2. 

Second, we replace the second sentence of the Con- 
clusion, see id. at 1057, with the following: 

We do not vacate the new ozone standards because 
the parties have not shown that the standard is 
likely to engender costly compliance activities in 
light of our determination that it can be enforced 
only in conformity with Subpart 2. 

As with the PM2.5 NAAQS, our decision not to vacate 
the ozone NAAQS “is without prejudice to the ability of 
any party to apply for vacatur in the future, should 
circumstances develop in which the presence of this 

82a 

standard threatens a more imminent harm.” American 
Trucking Ass’ns, Inc. v. EPA, No. 97-1440 (D.C. Cir. 
Jun. 18, 1999). 

III. Beneficent Health Effects 

The arguments in the EPA’s petition for rehearing 
give us no reason to doubt the correctness of our con- 
clusion that “all identifiable effects,” as used in CAA 
§108(a)(2), “on its face . . . include[s] beneficent 
effects.” 175 F.3d at 1051. Nor do those arguments 
warrant consideration in a published opinion. We ex- 
press no opinion, of course, upon the effect, if any, that 
studies showing the beneficial effects of tropospheric 
ozone, see id. at 1052, might have upon any ozone 
standard the EPA may promulgate on remand. 

IV. Conclusion 

For the above reasons, the EPA’s petition for 
rehearing is 

Granted in part and denied in part. 

83a 

TATEL, Circuit Judge, concurring in part and dis- 
senting in part: 

I concur in the partial grant of rehearing with respect 
to enforcement of the revised ozone standard because, 
as modified, the opinion now leaves open the possibility 
that EPA can enforce the new ozone NAAQS without 
conflicting with Subpart 2’s classifications and attain- 
ment dates. While I too think that we have jurisdiction 
to decide the enforcement issue, I write separately 
because I do not entirely agree with the rationale of the 
modified panel opinion. 

The panel understood EPA’s original position to be 
that, although Subpart 2 limited the Agency’s en- 
forcement of the pre-existing one-hour 0.12 ppm ozone 
NAAQS, it “has no effect upon the EPA’s authority to 
enforce a revised primary ozone NAAQS.” American 
Trucking Associations v. EPA, 175 F.3d 1027, 1048 
(“ATA”). That interpretation, the panel held, not only 
conflicted with section 7511(a)(1)’s text and legislative 
history, see id., 175 F.3d at 1048-49, but by leaving the 
Agency free to “requir[e] areas to comply either more 
quickly or with a more stringent ozone NAAQS,” it 
defied Congress’s clear intent to “extend[ ] the time for 
nonattainment areas to comply with the 0.12 ppm ozone 
NAAQS.” Id. at 1049. 

Having rejected the Agency’s interpretation, the 
panel went on to agree with petitioners that Subpart 2 
embodies “a comprehensive enforcement scheme” that 
“specifically provides classifications and dates for all 
areas designated nonattainment under any ozone 
NAAQS.” Id. at 1049, 1048 (emphasis added). This 
holding meant that areas not covered by Table 1 in 

84a 

Subpart 2—i.e. those with one-hour ozone design values 
below 0.121 ppm-were completely exempt from any 
ozone regulation whatsoever. Although the panel 
acknowledged that EPA must continue to revise the 
NAAQS, see id. at 1047, it concluded that the revised 
standard “cannot be enforced by virtue of [Subpart 2].” 
Id. at 1057. 

After reading EPA’s petition for rehearing and the 
various responses, I no longer believe that it was “the 
unambiguously expressed intent of Congress” to com- 
mand EPA to revise the ozone standards, while deny- 
ing it the power to enforce them. Chevron U.S.A., Inc. 

v. NRDC, 467 U.S. 837, 842. Table 1 specifically pro- 
vides classifications and attainment dates for some 
areas, but as EPA points out, “it establishes no attain- 
ment dates or classifications for nonattainment areas 
with ‘design values’ lower than 0.121 ppm.” EPA Pet. 
Reh’g at 22-23. As the Agency argues, it is thus diffi- 
cult to see how Subpart 2 can “specifically provide[ ]” 
attainment dates for areas that are designated non- 
attainment under the new standard but are not covered 
by Table 1. See id. at 22-24. This gap in Table 1 makes 
it at least ambiguous whether Subpart 2 “specifically 
provide[s]” classifications and attainment dates for all 
areas exceeding the revised 0.08 ppm ozone NAAQS. 

EPA also points out that treating Subpart 2 as the 
exclusive enforcement scheme for all areas leads to 
“irrational and contradictory consequences.” Id. at 23. 
Subpart 2 provides that “[e]ach area designated non- 
attainment for ozone pursuant to section 7407(d) of this 
title shall be classified . . . under table 1, by operation 
of law. . . .” 42 U.S.C. § 7511(a)(1). Even if the panel 

is correct that the reference to section 7407(d) includes 

85a 

designations under a revised NAAQS pursuant to 
section 7407(d)(1)(A), see Slip Op. on Reh’g at 9-10, the 
fact remains that the only “nonattainment areas for 
which classifications [and attainment dates] are specifi- 
cally provided under” Table 1 are those having one- 
hour ozone design values of 0.121 ppm or greater. 
ATA, 175 F.3d at 1048 (quoting 42 U.S.C. § 
7502(a)(1)(C), (a)(2)(D)). Classifying other areas “under 
table 1, by operation of law” is thus impossible or, at the 
very least, not “unambiguously” “specifically provided 
for.” And although, as the panel noted, “a title [of a 
statute or section] cannot be allowed to create an 
ambiguity in the first place,” id., at 1050, the ambiguity 
in this statute—Can section 7511(a)(1) be applied 
literally to areas that have attained the old standard 
but fail to meet the new one?—appears in the text of 
Subpart 2 itself. 

Moreover, EPA has offered a plausible interpretation 
of the statute that reasonably reconciles the provisions 
of Subparts 1 and 2. In its Petition for Rehearing, the 
Agency states that “Subpart 2 addresses continued 
nonattainment for the primary one-hour ozone stan- 
dard,” EPA Pet. Reh’g at 20, while Subpart 1 provides 
implementation authority for the new ozone standard in 
areas that have already attained the old one, see id. at 
20-22. The Agency articulated this same reading of the 
statute in its original brief, stating that “consistent with 
Congress’ intent, EPA interpreted the Subpart 2 
provisions to remain in place for areas not attaining the 
one-hour standard, and concluded the one-hour stan- 
dard should continue to apply until EPA determines 
that an area attains that standard, thus facilitating 
continued implementation of the relevant Subpart 2 
measures.” EPA Ozone Brief at 72. The final 

86a 

rulemaking—the Agency action we are reviewing 
here—is even clearer about the relationship between 
Subparts 1 and 2: 

[A]t the time of the proposal of the new O3 stan- 
dard, EPA had proposed an interpretation of the 
Act in the proposed Interim Implementation Policy 
(61 FR 65764, December 13, 1996) under which the 
provisions of subpart 2 of part D of Title I of the Act 
would not apply to existing O3 nonattainment areas 
once a new O3 standard becomes effective. 

In light of comments received regarding the inter- 
pretation proposed in the Interim Implementation 
Policy, EPA has reconsidered that interpretation 
and now believes that the Act should be interpreted 
such that the provisions of subpart 2 continue to 
apply to O3 nonattainment areas for purposes of 
achieving attainment of the current 1-hour stan- 
dard. As a consequence, the provisions of subpart 2, 
which govern implementation of the 1-hour O3 
standard in O3 nonattainment areas, will continue to 
apply as a matter of law for so long as an area is not 
attaining the 1-hour standard. Once an area attains 
that standard, however, the purpose of the pro- 
visions of subpart 2 will have been achieved and 
those provisions will no longer apply. However, the 
provisions of subpart 1 of part D of Title I of the Act 
would apply to the implementation of the new 8- 
hour O3 standards. 

To facilitate the implementation of those provi- 
sions and to ensure a smooth transition to the im- 
plementation of the new 8-hour standard, the 1-hour 
standard should remain applicable to areas that are 
not attaining the 1-hour standard. Therefore, the 1- 

87a 

hour standard will remain applicable to an area until 
EPA determines that it has attained the 1-hour 
standard, at which point the 1-hour standard will no 
longer apply to that area. 

62 Fed. Reg. 38,873 (1997), cited in EPA Ozone Brief at 

72. See also 40 C.F.R. § 50.9(b) (continuing to apply the 
one-hour 0.12 ppm standard until it is attained). 

To be sure, EPA’s original brief did seem to advance 
the position the panel rejected—that in enforcing the 
new ozone NAAQS, the Agency is free to disregard 
altogether Subpart 2’s timetable. See EPA Ozone Brief 
at 69-71. Given the clarity of the final rule, however, I 
no longer believe that EPA actually intended to argue 
that it could subvert Subpart 2’s schedule in enforcing 
the new ozone NAAQS. When EPA’s lawyers said in 
the original brief that Subpart 2 is inapplicable to 
nonattainment areas under the new ozone standard, I 
assume they must have meant that even under the new 
standard, Subpart 2 continues to apply to areas covered 
by Table 1—not that Subpart 2 no longer applies at all. 
Viewed this way, EPA’s original brief and its petition 
for rehearing are perfectly consistent with the final 
rule: all three interpret the Act to mean that Subpart 2 
still applies to an area until it attains the one-hour 0.12 
ppm standard. This interpretation puts to rest the 
panel’s concern that Subpart 2’s attainment schedule 
“would have been stillborn had the EPA revised the 
ozone NAAQS immediately after the Congress enacted 
the 1990 amendments.” ATA, 175 F.3d at 1050. 

The Agency’s petition also explains the practical con- 
sequences of its interpretation of Subpart 2. Although 
EPA may not enforce a stricter ozone standard in Los 
Angeles earlier than the year 2012, see id. at 1049, the 

88a 

Agency need not wait for Los Angeles to achieve the 
old standard before requiring the rest of the country to 
move toward cleaner air. Cf. EPA Pet. Reh’g at 25 
(suggesting that Los Angeles “is the only area of the 
nation” where compliance with the 0.08 ppm NAAQS 
under Subpart 1 could possibly be required at the same 
time as compliance with the 0.12 ppm NAAQS under 
Subpart 2). In other words, Table 1 functions as a safe 
harbor for areas like Los Angeles whose ozone levels 
exceed 0.121 ppm. 

To sum up, the panel rejected what it was led to 
believe was EPA’s view that Subpart 2 applied only to 
nonattainment areas under the old standard but no 
longer applies at all under the new standard. The panel 
held instead that Subpart 2 applies to all nonattain- 
ment areas under any standard, foreclosing imple- 
mentation of a new standard in any area not covered by 
Table 1. EPA has now clarified its interpretation of the 
Act. A middle ground originally articulated in its final 
rulemaking, the Agency’s position harmonizes its gen- 
eral enforcement authority under Subpart 1 with the 
specific provisions of Subpart 2. Subpart 2 continues to 
govern those areas covered by Table 1, just as it did 
under the old NAAQS, but in areas that have attained 
the old standard, nothing precludes enforcement of the 
new standard under Subpart 1. 

I would have granted rehearing and held that the 
Agency’s position represents a reasonable interpreta- 
tion of an ambiguous statute. See Chevron, 467 U.S. at 
844 (upholding EPA’s construction of NAAQS attain- 
ment provisions of the Clean Air Act, stating that “a 
court may not substitute its own construction of a 
statutory provision for a reasonable interpretation 

89a 

made by the administrator of an agency.”). I none- 
theless concur in the judgment because the revised 
opinion’s statement that “the EPA can enforce a re- 
vised primary ozone NAAQS only in conformity with 
Subpart 2” leaves open the possibility that the new 
ozone standard can be implemented in areas that have 
attained the old standard. 

For the reasons set forth in my statement dissenting 
from the denial of rehearing en banc, I respectfully 
dissent from the denial of rehearing as to Part I of the 
panel opinion (“Delegation”). 

90a 

UNITED STATES COURT OF APPEALS 
FOR THE DISTRICT OF COLUMBIA CIRCUIT 

No. 97-1440 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

Nos. 97-1440, 97-1546, 97-1548, 97-1551 to 97-1553, 
97-1555, 97-1559, 97-1561, 97-1562, 97-1565, 97-1567, 
97-1571, 97-1573, 97-1574, 97-1576, 97-1578, 97-1579, 
97-1582,97-1585 to 97-1588, 97-1592, 
97-1594, 97-1596 to 97-1598 

97-1441 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

91a 

Nos. 97-1441, 97-1502, 97-1505, 97-1508 to 97-1510, 
97-1512 to 97-1514, 97-1518, 97-1519, 97-1526, 
97-1531, 

97-1539, 97-1566, 97-1568, 97-1570, 97-1572, 
97-1575, 

97-1584, 97-1589, 97-1591, 97-1595, 97-1619 

On Respondent EPA’s Suggestion for Rehearing 
En Banc 

[Filed October 29, 1999] 

Before: EDWARDS, Chief Judge, WALD, SILBERMAN, 
WILLIAMS, GINSBURG, SENTELLE, HENDERSON, 
RANDOLPH, ROGERS, TATEL, and GARLAND, Circuit 
Judges. 

Circuit Judges WALD and KAREN LECRAFT 
HENDERSON did not participate in this matter. 

Chief Judge HARRY T. EDWARDS and Circuit Judges 
SILBERMAN, ROGERS, TATEL, and GARLAND would 
grant the suggestion. 

A statement of Circuit Judge SILBERMAN dissenting 
from the denial of rehearing en banc is attached. 

A statement of Circuit Judge SILBERMAN dissenting 
from the denial of rehearing en banc is attached. 

A statement of Circuit Judge TATEL dissenting from 
the denial of rehearing en banc, in which Chief Judge 
EDWARDS and Circuit Judge GARLAND join, is 
attached. 

92a 

PER CURIAM 

Respondent EPA’s Suggestion for Rehearing En 
Banc and the responses thereto have been circulated to 
the full court. The taking of a vote was requested. 
Thereafter, a majority of the judges of the court in 
regular active service did not vote in favor of the 
suggestion. Upon consideration of the foregoing, it is 

ORDERED that the suggestion be denied. 

SILBERMAN, Circuit Judge, dissenting from the 
denial of rehearing en banc: 

The panel’s reliance on the nondelegation doctrine to 
reject EPA’s interpretation of section 109 of the Clean 
Air Act is rather ingenious, but I regret that it seems to 
me to be fundamentally unsound. I do not think that 
doctrine can be employed to force an agency to narrow 
a broad legislative delegation from Congress. 

The doctrine, as Judge Tatel in dissent pointed out, 
American Trucking Associations v. EPA, 175 F.3d 
1027, 1057-58 (D.C. Cir. 1999) (“ATA”) (Tatel, J., dis- 
senting in part), is at this stage of constitutional 
“evolution” not in particularly robust health. Justice 
Rehnquist heroically attempted to inject vitality into 
the doctrine in his powerful concurrence in the Benzene 
case, see Industrial Union Dep’t, AFL-CIO v. Ameri- 
can Petroleum Inst., 448 U.S. 607, 671 (1980). But, sad 
to say, his view is not shared by a majority of the Court 
which has acknowledged only a theoretical limitation on 
the scope of congressional delegations to the executive 
branch. See Mistretta v. United States, 488 U.S. 361, 
416 (1989) (Scalia, J., dissenting) (“What legislated stan- 
dard, one must wonder, can possibly be too vague to 

93a 

survive judicial scrutiny, when we have repeatedly up- 
held, in various contexts, a ‘public interest’ standard?”). 

To be sure, the plurality in the Benzene case ostensi- 
bly relied on the doctrine to support its interpretation 
of the Occupational Safety and Health Act. See Ben- 
zene, 448 U.S. at 645-46. But a careful reading of the 
plurality opinion (not, of course, an opinion of the Court, 
which would bind us) reveals that the doctrine was only 
a makeweight, tossed into the analysis, in light of 
Justice Rehnquist’s concurrence, to help justify the 
result. The plurality, disturbed at the seemingly draco- 
nian impact of the Secretary of Labor’s standard as 
applied to several industries, analytically conflated the 
scope of the Secretary’s discretion—the legitimate 
concern of the nondelegation doctrine—with the regula- 
tory consequences of his interpretation of the statute. 
Id. at 645. The latter concern is not really germane to 
the doctrine; indeed, the Secretary was actually claim- 
ing he had less discretion than the plurality thought he 
had. Accordingly, the Benzene plurality opinion gives 
only lip service to the nondelegation doctrine; the 
boundaries limiting the scope of congressional delega- 
tion to the executive branch remain only dimly per- 
ceivable. I agree with Judge Tatel that the terminology 
of this section of the Clean Air Act does not come so 
close to those boundaries to raise a serious constitu- 
tional problem. 

If it did, and we were faced with two conflicting 
interpretations of the statute—both plausible—I have 
no doubt that a constitutionally dubious agency inter- 
pretation could be rejected even in a post-Chevron era. 
The majority questions that proposition—and confuses 
the issue—by stating that “the approach of the Benzene 

94a 

case . . . has given way to the approach of Chevron.” 
Slip Op. on Reh’g at 8. The Supreme Court’s opinion in 
Rust v. Sullivan, 500 U.S. 173, 191 (1991), is to the 
contrary. See also infra at 16 (Tatel, J., dissenting from 
denial of rehearing en banc) (citing Mistretta, 488 U.S. 
at 373 n.7). In other words, the constitutional avoidance 
canon trumps Chevron deference. But that principle is 
not relevant to this case. Even assuming the statute 
was problematic, the panel was not faced with two 
competing constructions, one of which might be thought 
to avoid constitutional difficulty. Indeed, the panel 
concluded that there are no intelligible principles “ap- 
parent from the statute” that brought EPA’s discretion 
within constitutionally acceptable limits. ATA, 175 
F.3d at 1034. If the panel believed that was so, it 
should have held the statute unconstitutional. Instead 
the panel, purporting to rely on Chevron, remanded to 
EPA directing that agency to come up with an artifi- 
cially narrow interpretation with various suggestions 
offered by the panel to accomplish that end.1 Id. at 
1038-40. By so doing, I believe the panel undermines 
the purpose of the nondelegation doctrine. 

That purpose is, of course, to ensure that Congress 
makes the crucial policy choices that are carried into 
law. The ability to make those policy choices (even if 
only at a broad level of generality) is what is meant by 
legislative power. See U.S. Const. art. I, § 1 (“All 
legislative Powers herein granted shall be vested in a 
Congress of the United States.”). It hardly serves— 
indeed, it contravenes—that purpose to demand that 

1 Like the plurality opinion in Benzene, these suggestions seem 
more directed to encouraging wiser policy choices than inter- 
preting the statute at issue. 

95a 

EPA in effect draft a different, narrower version of the 
Clean Air Act.2 Under that view Congress would be 
able to delegate almost limitless policymaking authority 
to an agency, so long as the agency provides and con- 
sistently applies an “intelligible principle.” 3 

That is not to say that EPA is totally free to exercise 
its authority at any point on the discretionary con- 
tinuum that Congress delegated to it in the Clean Air 
Act. The Administrative Procedure Act’s arbitrary and 
capricious standard also limits the agency’s actions. As 
we have observed, the broader the substantive statu- 
tory delegation the more likely that the agency’s policy 
choices will be confined by the APA, rather than the 
substantive statute. See National Ass’n of Regulatory 
Utility Com’rs v. ICC, 41 F.3d 721, 727 (D.C. Cir. 1994) 
(“Whether an agency action is to be judged as reason- 
able, in accordance with the APA’s general arbitrary 
and capricious standard, or whether it is to be examined 
as a permissible interpretation of the statute vel non 
depends, at least theoretically, on the scope of the 

2 The panel acknowledges this purpose but, relying on an old 
district court opinion as primary support, claims that its approach 
preserves two other rationales of the doctrine, limiting the ability 
of agencies to exercise delegated authority arbitrarily and provid- 
ing meaningful standards for judicial review. See ATA, 175 F.3d at 
1038 (citing Amalgamated Meat Cutters v. Connally, 337 F. Supp. 
737, 758-59 (D.D.C. 1971). But these “purposes” are obviously de- 
rivative of the doctrine’s primary function of ensuring that Con- 
gress makes key policy decisions. It is, after all, only this so-called 
“third” purpose, see id., that has any connection to the doctrine’s 
constitutional source. 

3 It is true that we used a similar approach in Industrial 
Union, UAW v. OSHA (“Lockout-Tagout I”), 938 F.2d 1310 (D.C. 
Cir. 1991). Although one could distinguish that case, I think it 
rests on a similarly flawed analysis of the doctrine. 

96a 

specific congressional delegation implicated.”). In that 
regard, I am quite uncertain whether EPA’s regulatory 
choice meets that test. Judge Tatel’s emphasis on the 
agency’s extensive procedures does not appear to me to 
answer the question. It would not matter whether the 
agency “actually adhered to a disciplined decision- 
making process,” ATA, 175 F.3d at 1059, if its final 
product was unreasonable. If we were to rehear the 
case, I would focus on that issue. 

Doctrine aside, then, what is the practical difference 
between my approach and the panel’s? The answer, I 
think, is that the panel engages—and by retaining 
jurisdiction promises to continue to engage, see id. at 
1057—in a more searching review than the arbitrary 
and capricious standard would permit. By treating this 
case as a statutory interpretation question laden with 
constitutional implications the panel implicitly asserts a 
greater role for a reviewing court than is justified. 

* * * * 

I respectfully dissent from our denial of rehearing en 
banc. 

97a 

TATEL, Circuit Judge, with whom HARRY T. 
EDWARDS, Chief Judge, and GARLAND, Circuit Judge, 
join, dissenting from the denial of rehearing en banc: 

In explaining why they remain convinced that the 
Clean Air Act contains an unconstitutional delegation of 
legislative power, my colleagues merely repeat that 
EPA has failed to articulate a sufficiently limiting prin- 
ciple. See Slip Op. on Reh’g at 6-7. They then launch 
into a discussion of the proper remedy once a court 
encounters a problematic legislative delegation and 
conclude that “the approach of the Benzene case . . . 
has given way to the approach of Chevron.” Slip Op. on 
Reh’g at 8. But see supra at 14-15 (Silberman, J., dis- 
senting from the denial of rehearing en banc); Mistretta 

v. United States, 488 U.S. 361, 373 n.7 (1989) (“In recent 
years, our application of the nondelegation doctrine 
principally has been limited to the interpretation of 
statutory texts, and more particularly, to giving narrow 
constructions to statutory delegations that might other- 
wise be thought to be unconstitutional. See, e.g., [the 
Benzene case.]”). 

The issues discussed by my colleagues have no 
relevance to the constitutional question we face. As I 
pointed out in my dissent, the Clean Air Act’s require- 
ment that EPA set air quality standards “requisite to 
protect the public health” with “an adequate margin of 
safety” based on criteria that “accurately reflect the 
latest scientific knowledge” is far more specific than the 
sweeping statutory delegations consistently upheld by 
the Supreme Court for more than sixty years. 42 
U.S.C. § 7409(b)(1), § 7408(a)(2). See, e.g., National 
Broadcasting Co. v. United States, 319 U.S. 190, 225-26 
(1943) (upholding delegation to the FCC to regulate 

98a 

broadcast licensing in the “public interest”); American 
Trucking Associations, Inc. v. EPA, 175 F.3d 1027, 
1057-58 (D.C. Cir. 1999) Tatel, J., dissenting in part) 
(collecting cases). In language particularly relevant to 
the highly technical and scientific process of setting 
national ambient air quality standards, the Supreme 
Court in Mistretta said this about the nondelegation 
doctrine: “[O]ur jurisprudence has been driven by a 
practical understanding that in our increasingly com- 
plex society, replete with ever changing and more 
technical problems, Congress simply cannot do its job 
absent an ability to delegate power under broad 
general directives.” 488 U.S. at 372. Such extensive 
and unambiguous Supreme Court precedent is more 
than enough to sustain the Clean Air Act’s delegation of 
authority to the EPA. For purposes of constitutional 
analysis, we thus have no need to require that EPA 
state “a far more determinate basis for decision” 
beyond the intelligible principle Congress provided in 
the Clean Air Act. ATA, 175 F.3d at 1037. Nor have 
we any reason to consider what remedies might be 
available were we faced with a statute that failed to 
meet constitutional standards. Unless petitioners can 
persuade the Supreme Court to return to the days of 
Schechter Poultry, this “inferior” court has no authority 
to demand anything more from either EPA or 
Congress. 

Neither American Lung Ass’n v. EPA, 134 F.3d 388 
(D.C. Cir. 1998), nor the Benzene case, both heavily 
relied upon by petitioners in their opposition to the 
suggestion for rehearing en banc, supports the panel’s 
opinion. No one in American Lung doubted the consti- 
tutionality of section 109’s directive that EPA establish 
NAAQS “requisite to protect the public health.” Ap- 

99a 

plying the familiar arbitrary and capricious standard, 
we held only that the Agency, in setting the sulfur 
dioxide NAAQS, had failed adequately to explain its 
application of section 109. See American Lung, 134 
F.3d at 392. The Benzene plurality stated nothing more 
than that section 3(8) of the OSHA statute implicitly re- 
quires the Agency to make a threshold finding that a 
substance to be regulated causes “significant risks of 
harm.” 448 U.S. at 641. In support of this inference, 
the plurality pointed to the statute’s structure, context, 
and legislative history, see id. at 642-45, adding that a 
broader reading “might” amount to an unconstitutional 
delegation, id. at 646. The conclusion that Congress 
may constitutionally delegate authority to OSHA to 
regulate “significant” risks of harm hardly supports the 
panel’s holding that Congress may not constitutionally 
delegate authority to EPA to issue NAAQS “requisite” 
to protect the public health—-a standard more restric- 
tive than the one the Supreme Court derived and 
approved in the Benzene case. 

The panel’s nondelegation holding plainly “involves a 
question of exceptional importance” warranting en banc 
review. Fed. R. App. P. 35(a). Not only did the panel 
depart from a half century of Supreme Court separa- 
tion-of-powers jurisprudence, but in doing so, it 
stripped the Environmental Protection Agency of much 
of its ability to implement the Clean Air Act, this 
nation’s primary means of protecting the safety of the 
air breathed by hundreds of millions of people. See 
H.R. Rep. No. 101-490, pt. 1, at 144-45 (1990). 

100a 

UNITED STATES COURT OF APPEALS 
FOR THE DISTRICT OF COLUMBIA CIRCUIT 

No. 97-1440 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

Nos. 97-1440, 97-1546, 97-1548, 97-1551 to 97-1553, 
97-1555, 97-1559, 97-1561, 97-1562, 97-1565, 97-1567, 
97-1571, 97-1573, 97-1574, 97-1576, 97-1578, 97-1579, 
97-1582,97-1585 to 97-1588, 97-1592, 
97-1594, 97-1596 to 97-1598 

97-1441 

AMERICAN TRUCKING ASSOCIATIONS, INC., ET AL., 
PETITIONERS 

v. 

UNITED STATES ENVIRONMENTAL PROTECTION 
AGENCY, RESPONDENT 

COMMONWEALTH OF MASSACHUSETTS, ET AL., 
INTERVENORS 

101a 

Nos. 97-1441, 97-1502, 97-1505, 97-1508 to 97-1510, 
97-1512 to 97-1514, 97-1518, 97-1519, 97-1526, 97-1531, 
97-1539, 97-1566, 97-1568, 97-1570, 97-1572, 97-1575, 
97-1584, 97-1589, 97-1591, 97-1595, 97-1619 

On Respondent EPA’s Suggestion for Rehearing 
En Banc 

[Filed October 29, 1999] 

BEFORE: EDWARDS, Chief Judge; WALD, SILBER- 
MAN, WILLIAMS, GINSBURG, SENTELLE, HENDERSON, 
RANDOLPH, ROGERS, TATEL and GARLAND, Circuit 
Judges. 

Circuit Judges WALD and KAREN LECRAFT 
HENDERSON did not participate in this matter. 

ORDER 

PER CURIAM 

Upon consideration of the petitions for rehearing en 
banc of intervenors-respondents New Jersey and Mas- 
sachusetts in Nos. 97-1440 and 97-1441, Citizens for 
Balanced Transportation, et al. in No. 97-1440 and the 
American Lung Association in Nos. 97-1440 and 97- 
1441, and the absence of a request by any member of 
the court for a vote, it is 

ORDERED that the petitions be denied. 

102a 

APPENDIX C 

The final rule revising the National Ambient Air 
Quality Standards for Particulate Matter provides: 

Therefore, 40 CFR Chapter I is amended as 
follows: 

PART 50—NATIONAL PRIMARY AND SECONDARY 
AMBIENT AIR QUALITY STANDARDS 

* * * 

4. Section 50.7 is added to read as follows: 

§ 50.7 National primary and secondary ambient air 
quality standards for particulate matter. 

(a) The national primary and secondary ambient air 
quality standards for particulate matter are: 

(1) 15.0 micrograms per cubic meter (•g/m3) annual 
arithmetic mean concentration, and 65 •g/m3 24-hour 
average concentration measured in the ambient air as 
PM2.5 (particles with an aerodynamic diameter less than 
or equal to a nominal 2.5 micrometers) by either: 

(i) A reference method based on Appendix L of this 
part and designated in accordance with part 53 of this 
chapter; or 

(ii) An equivalent method designated in accordance 
with part 53 of this chapter. 

(2) 50 micrograms per cubic meter (•g/m3) annual 
arithmetic mean concentration, and 150 •g/m3 24-hour 
average concentration measured in the ambient air as 

103a 

PM10 (particles with an aerodynamic diameter less than 
or equal to a nominal 10 micrometers) by either: 

(i) A reference method based on Appendix M of this 
part and designated in accordance with part 53 of this 
chapter; or 

(ii) An equivalent method designated in accordance 
with part 53 of this chapter. 

(b) The annual primary and secondary PM2.5 stan- 
dards are met when the annual arithmetic mean concen- 
tration, as determined in accordance with Appendix N 
of this part, is less than or equal to 15.0 micrograms per 
cubic meter. 

(c) The 24-hour primary and secondary PM2.5 stan- 
dards are met when the 98th percentile 24-hour concen- 
tration, as determined in accordance with Appendix N 
of this part, is less than or equal to 65 micrograms per 
cubic meter. 

(d) The annual primary and secondary PM10 stan- 
dards are met when the annual arithmetic mean concen- 
tration, as determined in accordance with Appendix N 
of this part, is less than or equal to 50 micrograms per 
cubic meter. 

(e) The 24-hour primary and secondary PM10 stan- 
dards are met when the 99th percentile 24-hour concen- 
tration, as determined in accordance with Appendix N 
of this part, is less than or equal to 150 micrograms per 
cubic meter. 

* * * 

62 Fed. Reg. 38,711 (July 18, 1997). 

104a 

APPENDIX D 

The final rule revising the National Ambient Air 
Quality Standards for Ozone provides: 

Therefore, for the reasons set forth in the preamble, 
title 40, chapter I, part 50 of the Code of Federal 
Regulations is amended as follows: 

PART 50—NATIONAL PRIMARY AND SECONDARY 
AMBIENT AIR QUALITY STANDARDS 

* * * 

3. Section 50.10 is added to read as follows: 

§ 50.10 National 8-hour primary and secondary ambient 
air quality standards for ozone. 

(a) The level of the national 8-hour primary and 
secondary ambient air quality standards for ozone, 
measured by a reference method based on Appendix D 
to this part and designated in accordance with part 53 
of this chapter, is 0.08 parts per million (ppm), daily 
maximum 8-hour average. 

(b) The 8-hour primary and secondary ozone 
ambient air quality standards are met at an ambient air 
quality monitoring site when the average of the annual 
fourth-highest daily maximum 8-hour average ozone 
concentration is less than or equal to 0.08 ppm, as 
determined in accordance with Appendix I to this part. 

* * * 

62 Fed. Reg. 38,894 (July 18, 1997). 

105a 

APPENDIX E 

Section 107(d) of the Clean Air Act provides: 

§ 7407. Air quality control regions 

* * * * * 

(d) Designations 

(1) Designations generally 

(A) Submission by Governors of initial designations 

following promulgation of new or revised standards 

By such date as the Administrator may reasonably 
require, but not later than 1 year after promulgation of 
a new or revised national ambient air quality standard 
for any pollutant under section 7409 of this title, the 
Governor of each State shall (and at any other time the 
Governor of a State deems appropriate the Governor 
may) submit to the Administrator a list of all areas (or 
portions thereof ) in the State, designating as— 

(i) nonattainment, any area that does not meet 
(or that contributes to ambient air quality in a 
nearby area that does not meet) the national pri- 
mary or secondary ambient air quality standard for 
the pollutant, 

(ii) attainment, any area (other than an area 
identified in clause (i)) that meets the national pri- 
mary or secondary ambient air quality standard for 
the pollutant, or 

(iii) unclassifiable, any area that cannot be 
classified on the basis of available information as 
meeting or not meeting the national primary or 

106a 

secondary ambient air quality standard for the 
pollutant. 

The Administrator may not require the Governor to 
submit the required list sooner than 120 days after 
promulgating a new or revised national ambient air 
quality standard. 

(B) Promulgation by EPA of designations 

(i) Upon promulgation or revision of a national 
ambient air quality standard, the Administrator shall 
promulgate the designations of all areas (or portions 
thereof ) submitted under subparagraph (A) as expedi- 
tiously as practicable, but in no case later than 2 years 
from the date of promulgation of the new or revised 
national ambient air quality standard. Such period may 
be extended for up to one year in the event the Ad- 
ministrator has insufficient information to promulgate 
the designations. 

* * * * * 

(C) Designations by operation of law 

(i) Any area designated with respect to any air 
pollutant under the provisions of paragraph (1)(A), (B), 
or (C) of this subsection (as in effect immediately before 
November 15, 1990) is designated, by operation of law, 
as a nonattainment area for such pollutant within the 
meaning of subparagraph (A)(i). 

(ii) Any area designated with respect to any air 
pollutant under the provisions of paragraph (1)(E) (as in 
effect immediately before November 15, 1990) is desig- 
nated by operation of law, as an attainment area for 

107a 

such pollutant within the meaning of subparagraph 
(A)(ii). 

(iii) Any area designated with respect to any air 
pollutant under the provisions of paragraph (1)(D) (as in 
effect immediately before November 15, 1990) is 
designated, by operation of law, as an unclassifiable 
area for such pollutant within the meaning of sub- 
paragraph (A)(iii). 

* * * * * 

(3) Redesignation 

* * * * * 

(E) The Administrator may not promulgate a 
redesignation of a nonattainment area (or portion 
thereof) to attainment unless— 

(i) the Administrator determines that the area 
has attained the national ambient air quality 
standard; 

(ii) the Administrator has fully approved the 
applicable implementation plan for the area under 
section 7410(k) of this title; 

(iii) the Administrator determines that the 
improvement in air quality is due to permanent and 
enforceable reductions in emissions resulting from 
implementation of the applicable implementation 
plan and applicable Federal air pollutant control 
regulations and other permanent and enforceable 
reductions; 

108a 

(iv) the Administrator has fully approved a 
maintenance plan for the area as meeting the 
requirements of section 7505a of this title; and 

(v) the State containing such area has met all 
requirements applicable to the area under section 
7410 of this title and part D of this subchapter. 

* * * * * 

(4) Nonattainment designations for ozone, carbon 

monoxide and particulate matter (PM-10) 

(A) Ozone and carbon monoxide 

(i) Within 120 days after November 15, 1990, 
each Governor of each State shall submit to the 
Administrator a list that designates, affirms or 
reaffirms the designation of, or redesignates (as 
the case may be), all areas (or portions thereof) 
of the Governor’s State as attainment, nonattain- 
ment, or unclassifiable with respect to the na- 
tional ambient air quality standards for ozone 
and carbon monoxide. 

(ii) No later than 120 days after the date the 
Governor is required to submit the list of areas 
(or portions thereof ) required under clause (i) of 
this subparagraph, the Administrator shall 
promulgate such designations, making such 
modifications as the Administrator may deem 
necessary, in the same manner, and under the 
same procedure, as is applicable under clause (ii) 
of paragraph (1)(B), except that the phrase “60 
days” shall be substituted for the phrase “120 
days” in that clause. If the Governor does not 

109a 

submit, in accordance with clause (i) of this sub- 
paragraph, a designation for an area (or portion 
thereof), the Administrator shall promulgate the 
designation that the Administrator deems 
appropriate. 

(iii) No nonattainment area may be redesig- 
nated as an attainment area under this sub- 
paragraph. 

* * * * * 

Section 108(a) of the Clean Air Act provides: 

§ 7408. 

Air quality criteria and control techniques 

(a) Air pollutant list; publication and revision by Ad- 
ministrator; issuance of air quality criteria for air 

pollutants 

(1) For the purpose of establishing national primary 
and secondary ambient air quality standards, the 
Administrator shall within 30 days after December 31, 
1970, publish, and shall from time to time thereafter 
revise, a list which includes each air pollutant— 

(A) emissions of which, in his judgment, cause or 
contribute to air pollution which may reasonably be 
anticipated to endanger public health or welfare; 

(B) the presence of which in the ambient air 
results from numerous or diverse mobile or station- 
ary sources; and 

(C) for which air quality criteria had not been 
issued before December 31, 1970, but for which he 
plans to issue air quality criteria under this section. 

110a 

(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 indi- 
cating 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. The criteria for an air pollutant, to 
the extent practicable, shall include information on— 

(A) those variable factors (including atmospheric 
conditions) which of themselves or in combination 
with other factors may alter the effects on public 
health or welfare of such air pollutant; 

(B) the types of air pollutants which, when 
present in the atmosphere, may interact with such 
pollutant to produce an adverse effect on public 
health or welfare; and 

(C) any known or anticipated adverse effects on 
welfare. 

* * * * * 

111a 

Section 109 of the Clean Air Act, 42 U.S.C. 7408, 
provides: 

§ 7409. 

National primary and secondary ambient air 

quality standards 

(a) Promulgation 

(1) The Administrator— 

(A) within 30 days after December 31, 1970, 
shall publish proposed regulations prescribing a 
national primary ambient air quality standard and a 
national secondary ambient air quality standard for 
each air pollutant for which air quality criteria have 
been issued prior to such date; and 

(B) after a reasonable time for interested per- 
sons to submit written comments thereon (but no 
later than 90 days after the initial publication of 
such proposed standards) shall by regulation 
promulgate such proposed national primary and 
secondary ambient air quality standards with such 
modifications as he deems appropriate. 

* * * * * 

(b) Protection of public health and welfare 

(1) National primary ambient air quality standards, 
prescribed under subsection (a) of this section shall be 
ambient air quality standards the attainment and 
maintenance of which in the judgment of the Adminis- 
trator, 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. 

112a 

* * * * * 

(d) Review and revision of criteria and standards; inde- 
pendent 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 Administra- 
tor may review and revise criteria or promulgate new 
standards earlier or more frequently than required 
under this paragraph. 

(2)(A) The Administrator shall appoint an 
independent scientific review committee composed of 
seven members including at least one member of the 
National Academy of Sciences, one physician, and one 
person representing State Air pollution control 
agencies. 

(B) Not later than January 1, 1980, and at five-year 
intervals thereafter, the committee referred to in 
subparagraph (A) shall complete a review of the criteria 
published under section 7408 of this title and the 
national primary and secondary ambient air quality 
standards promulgated under this section and shall 
recommend to the Administrator any new national 
ambient air quality standards and revisions of existing 
criteria and standards as may be appropriate under 

113a 

section 7408 of this title and subsection (b) of this 
section. 

(C) Such committee shall also (i) advise the 
Administrator of areas in which additional knowledge is 
required to appraise the adequacy and basis of existing, 
new, or revised national ambient air quality standards, 
(ii) describe the research efforts necessary to provide 
the required information, (iii) advise the Administrator 
on the relative contribution to air pollution concentra- 
tions of natural as well as anthropogenic activity, and 
(iv) advise the Administrator of any adverse public 
health, welfare, social, economic, or energy effects 
which may result from various strategies for attain- 
ment and maintenance of such national ambient air 
quality standards. 

* * * * * 

Section 172 of the Clean Air Act, 42 U.S.C. 7409, 
provides: 

§ 7502. 

Nonattainment plan provisions in general 

(a) Classifications and attainment dates 

(1) Classifications 

(A) On or after the date the Administrator 
promulgates the designation of an area as a non- 
attainment area pursuant to section 7407(d) of this 
title with respect to any national ambient air quality 
standard (or any revised standard, including a 
revision of any standard in effect on November 15, 
1990), the Administrator may classify the area for 
the purpose of applying an attainment date pursuant 
to paragraph (2), and for other purposes. In deter- 

114a 

mining the appropriate classification, if any, for a 
nonattainment area, the Administrator may consider 
such factors as the severity of nonattainment in such 
area and the availability and feasibility of the 
pollution control measures that the Administrator 
believes may be necessary to provide for attainment 
of such standard in such area. 

(B) The Administrator shall publish a notice in 
the Federal Register announcing each classification 
under subparagraph (A), except the Administrator 
shall provide an opportunity for at least 30 days for 
written comment. Such classification shall not be 
subject to the provisions of sections 553 through 557 
of Title 5 (concerning notice and comment) and shall 
not be subject to judicial review until the Admin- 
istrator takes final action under subsection (k) or (l) 
of section 7410 of this title (concerning action on plan 
submissions) or section 7509 of this title (concerning 
sanctions) with respect to any plan submissions 
required by virtue of such classification. 

(C) This paragraph shall not apply with respect 
to nonattainment areas for which classifications are 
specifically provided under other provisions of this 
part. 

(2) Attainment dates for nonattainment areas 

(A) The attainment date for an area designated 
nonattainment with respect to a national primary 
ambient air quality standard shall be the date by 
which attainment can be achieved as expeditiously as 
practicable, but no later than 5 years from the date 
such area was designated nonattainment under sec- 
tion 7407(d) of this title, except that the Administra- 

115a 

tor may extend the attainment date to the extent the 
Administrator determines appropriate, for a period 
no greater than 10 years from the date of designation 
as nonattainment, considering the severity of 
nonattainment and the availability and feasibility of 
pollution control measures. 

(B) The attainment date for an area designated 
nonattainment with respect to a secondary national 
ambient air quality standard shall be the date by 
which attainment can be achieved as expeditiously as 
practicable after the date such area was designated 
nonattainment under section 7407(d) of this title. 

(C) Upon application by any State, the Ad- 
ministrator may extend for 1 additional year (herein- 
after referred to as the “Extension Year”) the attain- 
ment date determined by the Administrator under 
subparagraph (A) or (B) if— 

(i) the State has complied with all 
requirements and commitments pertaining to the 
area in the applicable implementation plan, and 

(ii) in accordance with guidance published by 
the Administrator, no more than a minimal 
number of exceedances of the relevant national 
ambient air quality standard has occurred in the 
area in the year preceding the Extension Year. 

No more than 2 one-year extensions may be issued 
under this subparagraph for a single nonattainment 
area. 

(D) This paragraph shall not apply with respect 
to nonattainment areas for which attainment dates 

116a 

are specifically provided under other provisions of 
this part. 

(b) Schedule for plan submissions 

At the time the Administrator promulgates the 
designation of an area as nonattainment with respect to 
a national ambient air quality standard under section 
7407(d) of this title, the Administrator shall establish a 
schedule according to which the State containing such 
area shall submit a plan or plan revision (including the 
plan items) meeting the applicable requirements of 
subsection (c) of this section and section 7410(a)(2) of 
this title. Such schedule shall at a minimum, include a 
date or dates, extending no later than 3 years from the 
date of the nonattainment designation, for the sub- 
mission of a plan or plan revision (including the plan 
items) meeting the applicable requirements of subsec- 
tion (c) of this section and section 7410(a)(2) of this title. 

(c) Nonattainment plan provisions 

The plan provisions (including plan items) required to 
be submitted under this part shall comply with each of 
the following: 

(1) In general 

Such plan provisions shall provide for the imple- 
mentation of all reasonably available control measures 
as expeditiously as practicable (including such reduc- 
tions in emissions from existing sources in the area as 
may be obtained through the adoption, at a minimum, of 
reasonably available control technology) and shall pro- 
vide for attainment of the national primary ambient air 
quality standards. 

117a 

* * * * * 

Section 181 of Subpart 2, Part D, Title I of the Clean 
Air Act provides: 

Subpart 2–Additional Provisions for Ozone Nonattain- 
ment Areas 

§ 7511. 

Classifications and attainment dates 

(a) Classification and attainment dates for 1989 nonattain- 
ment areas 

(1) Each area designated nonattainment for ozone 
pursuant to section 7407(d) of this title shall be classi- 
fied at the time of such designation, under table 1, by 
operation of law, as a Marginal Area, a Moderate Area, 
a Serious Area, a Severe Area, or an Extreme Area 
based on the design value for the area. The design 
value shall be calculated according to the interpretation 
methodology issued by the Administrator most recently 
before November 15, 1990. For each area classified 
under this subsection, the primary standard attainment 
date for ozone shall be as expeditiously as practicable 
but not later than the date provided in table 1. 

118a 

TABLE 1 

———————————————————————— 

Area class 
Design value [FN*] 

Primary standard attainment date 

[FN**] 

———————————————————————— 

Marginal ..... 
0.121 up to 0.138 .......... 

3 years after November 15, 1990 

Moderate ..... 

0.138 up to 0.160 ......... 
6 years after November 15, 1990 

Serious ...... 
0.160 up to 0.180 .......... 

9 years after November 15, 1990 

Severe ....... 
0.180 up to 0.280 .......... 

15 years after November 15, 1990 

Extreme ...... 

0.280 and above............ 
20 years after November 15, 1990 

[FN*] The design value is measured in parts per million (ppm). 

[FN**] The primary standard attainment date is measured from 
November 15, 1990. 

(2) Notwithstanding table 1, in the case of a severe 
area with a 1988 ozone design value between 0.190 and 

0.280 ppm, the attainment date shall be 17 years (in lieu 
of 15 years) after November 15, 1990. 

(3) At the time of publication of the notice under 
section 7407(d)(4) of this title (relating to area designa- 
tions) for each ozone nonattainment area, the Admin- 
istrator shall publish a notice announcing the classifica- 
tion of such ozone nonattainment area. The provisions 
of section 7502(a)(1)(B) of this title (relating to lack of 
notice and comment and judicial review) shall apply to 
such classification. 

(4) If an area classified under paragraph (1)(Table 1) 
would have been classified in another category if the 
design value in the area were 5 percent greater or 5 
percent less than the level on which such classification 
was based, the Administrator may, in the Administra- 
tor’s discretion, within 90 days after the initial classi- 

119a 

fication, by the procedure required under paragraph 
(3), adjust the classification to place the area in such 
other category. In making such adjustment, the 
Administrator may consider the number of exceedances 
of the national primary ambient air quality standard for 
ozone in the area, the level of pollution transport 
between the area and other affected areas, including 
both intrastate and interstate transport, and the mix of 
sources and air pollutants in the area. 

(5) Upon application by any State, the Administra- 
tor may extend for 1 additional year (hereinafter 
referred to as the “Extension Year”) the date specified 
in table 1 of paragraph (1) of this subsection if— 

(A) the State has complied with all requirements 
and commitments pertaining to the area in the 
applicable implementation plan, and 

(B) no more than 1 exceedance of the national 
ambient air quality standard level for ozone has 
occurred in the area in the year preceding the Ex- 
tension Year. No more than 2 one-year extensions 
may be issued under this paragraph for a single non- 
attainment area. 

(b) New designations and reclassifications 

(1) New designations to nonattainment 

Any area that is designated attainment or 
unclassifiable for ozone under section 7407(d)(4) of 
this title, and that is subsequently redesignated to 
nonattainment for ozone under section 7407(d)(3) of 
this title, shall, at the time of the redesignation, be 
classified by operation of law in accordance with 

120a 

table 1 under subsection (a) of this section. Upon its 
classification, the area shall be subject to the same 
requirements under section 7410 of this title, subpart 
1 of this part, and this subpart that would have 
applied had the area been so classified at the time of 
the notice under subsection (a)(3) of this section, 
except that any absolute, fixed date applicable in 
connection with any such requirement is extended by 
operation of law by a period equal to the length of 
time between November 15, 1990, and the date the 
area is classified under this paragraph. 

* * * * * 

Section 307 of the Clean Air Act, 42 U.S.C. 7607, 
provides: 

§ 7607. Administrative proceedings and judicial 
review 

* * * * * 

(b) Judicial review 

(1) A petition for review of action of the 
Administrator in promulgating any national primary or 
secondary ambient air quality standard, * * * or any 
other nationally applicable regulations promulgated, or 
final action taken, by the Administrator under this 
chapter may be filed only in the United States Court of 
Appeals for the District of Columbia. A petition for 
review of the Administrator’s action in approving or 
promulgating any implementation plan under section 
7410 of this title or section 7411(d) of this title * * * or 
any other final action of the Administrator under this 
chapter (including any denial or disapproval by the 

121a 

Administrator under subchpater I of this chapter) 
which is locally or regionally applicable may be filed 
only in the United States Court of Appeals for the 
appropriate circuit. 

(2) Action of the Administrator with respect to 
which review could have been obtained under para- 
graph (1) shall not be subject to judicial review in civil 
or criminal proceedings for enforcement. 

* * * * * 

(d) Rulemaking 

(1) This subsection applies to— 

(A) the promulgation or revision of any national 
ambient air quality standard under section 7409 of 
this title, 

* * * * * 

The provisions of section 553 through 557 and section 
706 of Title 5 shall not, except as expressly provided in 
this subsection, apply to actions to which this sub- 
section applies. This subsection shall not apply in the 
case of any rule or circumstance referred to in sub- 
paragraphs (A) or (B) of subsection 553(b) of Title 5. 

(2) Not later than the date of proposal of any action 
to which this subsection applies, the Administrator 
shall establish a rulemaking docket for such action 
(hereinafter in this subsection referred to as a “rule”). 
Whenever a rule applies only within a particular State, 
a second (identical) docket shall be simultaneously 
established in the appropriate regional office of the 
Environmental Protection Agency. 

122a 

(3) In the case of any rule to which this subsection 
applies, notice of proposed rulemaking shall be 
published in the Federal Register, as provided under 
section 553(b) of Title 5, shall be accompanied by a 
statement of its basis and purpose and shall specify the 
period available for public comment (hereinafter 
referred to as the “comment period”). The notice of 
proposed rulemaking shall also state the docket num- 
ber, the location or locations of the docket, and the 
times it will be open to public inspection. The state- 
ment of basis and purpose shall include a summary of— 

(A) the factual data on which the proposed rule 
is based; 

(B) the methodology used in obtaining the data 
and in analyzing the data; and 

(C) the major legal interpretations and policy 
considerations underlying the proposed rule. 

The statement shall also set forth or summarize and 
provide a reference to any pertinent findings, recom- 
mendations, and comments by the Scientific Review 
Committee established under section 7409(d) of this 
title and the National Academy of Sciences, and, if the 
proposal differs in any important respect from any of 
these recommendations, an explanation of the reasons 
for such differences. All data, information, and docu- 
ments referred to in this paragraph on which the pro- 
posed rule relies shall be included in the docket on the 
date of publication of the proposed rule. 

(4)(A) The rulemaking docket required under para- 
graph (2) shall be open for inspection by the public at 
reasonable times specified in the notice of proposed 

123a 

rulemaking. Any person may copy documents con- 
tained in the docket. The Administrator shall provide 
copying facilities which may be used at the expense of 
the person seeking copies, but the Administrator may 
waive or reduce such expenses in such instances as the 
public interest requires. Any person may request cop- 
ies by mail if the person pays the expenses, including 
personnel costs to do the copying. 

(B)(i) Promptly upon receipt by the agency, all 
written comments and documentary information on the 
proposed rule received from any person for inclusion in 
the docket during the comment period shall be placed in 
the docket. The transcript of public hearings, if any, on 
the proposed rule shall also be included in the docket 
promptly upon receipt from the person who transcribed 
such hearings. All documents which become available 
after the proposed rule has been published and which 
the Administrator determines are of central relevance 
to the rulemaking shall be placed in the docket as soon 
as possible after their availability. 

(ii) The drafts of proposed rules submitted by the 
Administrator to the Office of Management and Budget 
for any interagency review process prior to proposal of 
any such rule, all documents accompanying such drafts, 
and all written comments thereon by other agencies 
and all written responses to such written comments by 
the Administrator shall be placed in the docket no later 
than the date of proposal of the rule. The drafts of the 
final rule submitted for such review process prior to 
promulgation and all such written comments thereon, 
all documents accompanying such drafts, and written 
responses thereto shall be placed in the docket no later 
than the date of promulgation. 

124a 

(5) In promulgating a rule to which this subsection 
applies (i) the Administrator shall allow any person to 
submit written comments, data, or documentary infor- 
mation; (ii) the Administrator shall give interested 
persons an opportunity for the oral presentation of 
data, views, or arguments, in addition to an opportunity 
to make written submissions; (iii) a transcript shall be 
kept of any oral presentation; and (iv) the Administra- 
tor shall keep the record of such proceeding open for 
thirty days after completion of the proceeding to 
provide an opportunity for submission of rebuttal and 
supplementary information. 

(6)(A) The promulgated rule shall be accompanied 
by (i) a statement of basis and purpose like that 
referred to in paragraph (3) with respect to a proposed 
rule and (ii) an explanation of the reasons for any major 
changes in the promulgated rule from the proposed 
rule. 

(B) The promulgated rule shall also be accompanied 
by a response to each of the significant comments, 
criticisms, and new data submitted in written or oral 
presentations during the comment period. 

(C) The promulgated rule may not be based (in 
part or whole) on any information or data which has not 
been placed in the docket as of the date of such 
promulgation. 

(7)(A) The record for judicial review shall consist 
exclusively of the material referred to in paragraph (3), 
clause (i) of paragraph (4)(B), and subparagraphs (A) 
and (B) of paragraph (6). 

125a 

(B) Only an objection to a rule or procedure which 
was raised with reasonable specificity during the period 
for public comment (including any public hearing) may 
be raised during judicial review. If the person raising 
an objection can demonstrate to the Administrator that 
it was impracticable to raise such objection within such 
time or if the grounds for such objection arose after the 
period for public comment (but within the time speci- 
fied for judicial review) and if such objection is of cen- 
tral relevance to the outcome of the rule, the Admin- 
istrator shall convene a proceeding for reconsideration 
of the rule and provide the same procedural rights as 
would have been afforded had the information been 
available at the time the rule was proposed. If the 
Administrator refuses to convene such a proceeding, 
such person may seek review of such refusal in the 
United States court of appeals for the appropriate 
circuit (as provided in subsection (b) of this section). 
Such reconsideration shall not postpone the effective- 
ness of the rule. The effectiveness of the rule may be 
stayed during such reconsideration, however, by the 
Administrator or the court for a period not to exceed 
three months. 

(8) The sole forum for challenging procedural 
determinations made by the Administrator under this 
subsection shall be in the United States court of appeals 
for the appropriate circuit (as provided in subsection (b) 
of this section) at the time of the substantive review of 
the rule. No interlocutory appeals shall be permitted 
with respect to such procedural determinations. In 
reviewing alleged procedural errors, the court may 
invalidate the rule only if the errors were so serious and 
related to matters of such central relevance to the rule 
that there is a substantial likelihood that the rule would 

126a 

have been significantly changed if such errors had not 
been made. 

(9) In the case of review of any action of the 
Administrator to which this subsection applies, the 
court may reverse any such action found to be— 

(A) arbitrary, capricious, an abuse of discretion, 
or otherwise not in accordance with law; 

(B) contrary to constitutional right, power, 
privilege, or immunity; 

(C) in excess of statutory jurisdiction, authority, 
or limitations, or short of statutory right; or 

(D) without observance of procedure required 
by law, if (i) such failure to observe such procedure 
is arbitrary or capricious, (ii) the requirement of 
paragraph (7)(B) has been met, and (iii) the condi- 
tion of the last sentence of paragraph (8) is met. 

(10) Each statutory deadline for promulgation of 
rules to which this subsection applies which requires 
promulgation less than six months after date of 
proposal may be extended to not more than six months 
after date of proposal by the Administrator upon a 
determination that such extension is necessary to 
afford the public, and the agency, adequate opportunity 
to carry out the purposes of this subsection. 

(11) The requirements of this subsection shall take 
effect with respect to any rule the proposal of which 
occurs after ninety days after August 7, 1977. 

* * * * *