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United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued October 10, 2003 Decided January 13, 2004
No. 02-1253
SIERRA CLUB,
PETITIONER
v.
ENVIRONMENTAL PROTECTION AGENCY AND
CHRISTINE TODD WHITMAN, ADMINISTRATOR,
US ENVIRONMENTAL PROTECTION AGENCY,
RESPONDENTS
On Petition for Review of an Order of the
Environmental Protection Agency
James S. Pew argued the cause for petitioner. With him
on the briefs was David S. Baron.
David J. Kaplan, Attorney, U.S. Department of Justice,
argued the cause for respondents. With him on the brief was
Michael W. Thrift, Counsel, U.S. Environmental Protection
Agency.
Bills of costs must be filed within 14 days after entry of judgment.
The court looks with disfavor upon motions to file bills of costs out
of time.
2
Before: HENDERSON, TATEL, and ROBERTS, Circuit Judges.
ROBERTS, Circuit Judge: Petitioner Sierra Club challenges
the Environmental Protection Agency’s promulgation, pursu-
ant to Section 112 of the Clean Air Act, of regulations
governing the emission of hazardous air pollutants from
primary copper smelters. This is the latest in a series of
challenges to rulemakings establishing emission standards for
hazardous air pollutants in various industries under the Clean
Air Act, see, e.g., Cement Kiln Recycling Coalition v. EPA,
255 F.3d 855 (D.C. Cir. 2001) (hazardous waste combustors);
National Lime Ass’n v. EPA, 233 F.3d 625 (D.C. Cir. 2000)
(portland cement manufacturing facilities); Sierra Club v.
EPA, 167 F.3d 658 (D.C. Cir. 1999) (medical waste incinera-
tors); Appalachian Power Co. v. EPA, 135 F.3d 791 (D.C.
Cir. 1998) (electric utility boilers). We review such chal-
lenges under a familiar test and may set aside the standards
only if we find them to be ‘‘arbitrary, capricious, an abuse of
discretion, or otherwise not in accordance with law.’’ 42
U.S.C. § 7607(d)(9)(A); see Motor Vehicle Mfrs. Ass’n v.
State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 41 (1982). ‘‘The
‘arbitrary and capricious’ standard deems the agency action
presumptively valid provided the action meets a minimum
rationality standard.’’ Natural Res. Def. Council, Inc. v.
EPA, 194 F.3d 130, 136 (D.C. Cir. 1999). After considering
Sierra Club’s arguments and reviewing the record, we reject
its challenges to the rulemaking in this case and conclude that
EPA’s emission standards are not arbitrary, capricious, an
abuse of discretion, or contrary to law. We therefore deny
the petition for review.
I. Background
A. Statutory Background
In 1970, Congress enacted Section 112 of the Clean Air Act
(CAA), Pub. L. No. 91-604, § 112, 84 Stat. 1676, 1685 (1970),
in an effort to reduce hazardous air pollutants (HAPs). See
Natural Res. Def. Council, Inc. v. EPA, 824 F.2d 1146, 1148
(D.C. Cir. 1987); H.R. Rep. No. 101-490, pt. 1, at 150 (1990)
(House Report). The statute defined HAPs as ‘‘air pollu-
3
tant[s] TTT which in the judgment of the Administrator
cause[ ], or contribute[ ] to, air pollution which may reason-
ably be anticipated to result in an increase in mortality or an
increase in serious irreversible, or incapacitating reversible,
illness.’’ Clean Air Act Amendments of 1977, Pub. L. No. 95-
95, § 401(c), 91 Stat. 685, 791 (1977). Section 112 required
EPA to publish a list containing ‘‘each hazardous air pollutant
for which [it] intends to establish an emission standard,’’ and
then — within a specified period — either to promulgate an
emission standard or to explain why the particular HAP is in
fact not hazardous. § 112(b)(1)(A)–(B), 84 Stat. at 1685.
EPA followed a risk-based analysis to set emission standards
under the statute, meaning that EPA considered levels of
HAPs at which health effects are observed, factored in an
‘‘ample margin of safety to protect the public health,’’ and set
emission restrictions accordingly. § 112(b)(1)(B), 84 Stat. at
1685; see Cement Kiln Recycling Coalition, 255 F.3d at 857
(CKRC).
This approach proved to be disappointing. See S. Rep. No.
101-228, at 3 (1989) (Senate Report) (‘‘Very little has been
done since the passage of the 1970 [CAA] to identify and
control hazardous air pollutants.’’). In part because of uncer-
tainty over appropriate levels of protection under a risk-based
regime, and ‘‘unrealistic’’ time frames mandating proposed
standards 180 days after listing a pollutant as hazardous,
little progress was made. Id. at 132. From 1970 to 1990,
EPA listed only eight HAPs, establishing emission standards
for seven of them. Id. at 131; House Report, at 322. As the
House Committee on Energy and Commerce summarized the
progress of limiting HAP emissions under Section 112: ‘‘List-
ing decisions have been few and far between. TTT No deci-
sion — is the history of this program.’’ House Report, at 151
(quoting a Nov. 7, 1983 Committee hearing). The Senate
counterpart was more understated but the verdict was essen-
tially the same: ‘‘Attainment of the health-based air quality
standards has proven more difficult than anticipatedTTTT’’
Senate Report, at 3.
4
The ineffectiveness of the risk-based approach created a
‘‘broad consensus that the program to regulate [HAPs] under
section 112 of the Clean Air Act should be restructured to
provide EPA with authority to regulate TTT with technology-
based standards.’’ Id. at 133 (emphasis added). In response,
Congress passed the Clean Air Act Amendments of 1990,
Pub. L. No. 101-549, 104 Stat. 2531 (1990) (1990 Amendments
or Amendments), to ‘‘strengthen and expand the Clean Air
Act’’ through a ‘‘technology-based TTT program.’’ House
Report, at 144. The 1990 Amendments made two ‘‘fundamen-
tal changes’’ to Section 112 in order to implement the technol-
ogy-based approach. Senate Report, at 133. First, rather
than look to EPA to identify and list HAPs, Congress did it
itself, establishing a list of 191 HAPs requiring emission
standards. See 42 U.S.C. § 7412(b). Second, the Amend-
ments established an emission standards implementation pro-
cess ‘‘based on the maximum reduction in emissions which
can be achieved by application of best available control tech-
nology.’’ Senate Report, at 133; see CKRC, 255 F.3d at 857.
Congress established a two-phase approach for setting
HAP emission standards under the 1990 Amendments. See
National Lime, 233 F.3d at 629. During the first phase,
EPA must promulgate technology-based emission standards
for categories of sources that emit HAPs. 42 U.S.C.
§ 7412(d); Senate Report, at 148. These emission standards
are to be based not on an assessment of the risks posed by
HAPs, but instead on the maximum achievable control tech-
nology (MACT) for sources in each category. Senate Report,
at 148 (‘‘The MACT standards are based on the performance
of technology, and not on the health and environmental
effects of hazardous air pollutants.’’). The standards, at a
minimum, must reflect the emissions limitation achieved by
the best-performing sources in a particular category (here,
primary copper smelters). The idea is to set limits that, as
an initial matter, require all sources in a category to at least
clean up their emissions to the level that their best perform-
ing peers have shown can be achieved. See 42 U.S.C.
§ 7412(d)(3); National Emission Standards for Hazardous Air
Pollutants for Primary Copper Smelting; Final Rule, 67 Fed.
5
Reg. 40,478, 40,479 (June 12, 2002) (codified at 40 C.F.R. pt.
63) (Final Rule).
The second phase then returns to a risk-based analysis.
That phase — which occurs within eight years after Section
7412(d) MACT standards are promulgated — requires EPA
to consider whether residual risks remain that warrant more
stringent standards than achieved through MACT. 42 U.S.C.
§ 7412(f). EPA must determine whether such standards are
required ‘‘in order to provide an ample margin of safety to
protect public health TTT or to prevent TTT an adverse
environmental effect.’’ Id. § 7412(f)(2)(A); see also Senate
Report, at 155 (‘‘[The Amendments] require[ ] [EPA] to pro-
tect against all significant environmental effects when setting
residual risk standards in the second phase.’’).
The issues in this case focus on the first phase of emission
standards promulgation. Within that phase, there are two
steps. Step one requires EPA to establish what has come to
be known as the MACT floor — the minimum level of
reduction required by statute. For existing sources, EPA
sets the MACT floor at ‘‘the average emission limitation
achieved by the best performing 5 sources’’ in a category
‘‘with fewer than 30 sources.’’ 42 U.S.C. § 7412(d)(3)(B).
Once EPA has set the MACT floor, it may then impose
stricter standards — so-called ‘‘beyond-the-floor’’ limits — if
the Administrator determines them to be achievable after
‘‘taking into consideration the cost TTT and any non-air quali-
ty health and environmental impacts and energy require-
ments.’’ Id. § 7412(d)(2); see CKRC, 255 F.3d at 858. These
‘‘beyond-the-floor’’ limits in phase one under Section
7412(d)(2) are distinct from the risk-based limits to be set
eight years later under Section 7412(f)(2) during phase two.
B. Regulatory Background
In 1998, EPA announced proposed emission standards for
primary copper smelters and initiated notice-and-comment
procedures. See National Emission Standards for Hazardous
Air Pollutants for Source Categories: National Emission
Standards for Primary Copper Smelters, 63 Fed. Reg. 19,582
(Apr. 20, 1998) (Proposed Rule). When EPA presented the
6
Proposed Rule, six primary copper smelters operated in the
United States. Id. at 19,583/3. During the public comment
period, four of them suspended operations. Final Rule, 67
Fed. Reg. at 40,479/3. The rulemaking only concerned those
primary copper smelters that use ‘‘batch copper converters.’’
Id.
Such smelters produce copper from raw copper ore, which
typically contains less than one percent copper. Proposed
Rule, 63 Fed. Reg. at 19,583. At the mine site, copper sulfide
ore is processed into copper concentrate — a form of copper
ore with a higher copper content. After shipping to the
primary copper smelter, the copper concentrate is further
processed into a slurry and mixed with ‘‘fluxes’’ — materials
that facilitate the formation of a slag containing impurities
from the ore. The further refined concentrate is placed in a
copper concentrate dryer to remove some of the moisture
content, and the copper concentrate then moves to the flash
smelting furnace, where it is heated (at almost 1,830 degrees
Fahrenheit) until molten.
In the molten state, most of the remaining impurities form
into a slag. The slag is lighter than the molten copper, so it
rises to the surface and is removed to a slag cleaning vessel
or a slag pile (depending on the primary smelter). The
molten copper then moves to the batch converter, which
removes any remaining impurities by blowing oxygen through
the molten copper, forming additional slag that is skimmed
off. That process of blowing and skimming is repeated until
the copper is 96 to 98 percent pure.
Melting rocks and minerals at nearly 2,000 degrees Fahr-
enheit not surprisingly produces exhaust gas, which EPA
refers to as ‘‘off-gases.’’ There are two types of off-gases
generated by the smelting process: (1) process emissions and
(2) fugitive emissions. Process emissions are the primary
exhaust gas streams generated by copper dryers, smelting
furnaces, slag cleaning vessels, and batch converters. These
gas streams are captured and routed to control devices before
being emitted into the atmosphere. Fugitive emissions are
off-gases that escape from the primary exhaust gas streams,
7
entering the atmosphere without going through emissions
control. The off-gases from smelting copper sulfide ore
contain concentrated sulfur dioxide — so much that some off-
gases are routed to an adjacent plant producing sulfuric acid.
The off-gases also contain metallic impurities — including
lead and arsenic — that had been trapped in the ore but are
released during smelting in the form of particulate matter
(PM) in the off-gases. These metallic impurities released
during the smelting process are the HAPs that are the focus
of the subject rulemaking. See id. at 19,584–85.
Copper smelters use several different methods of PM
control to regulate process emissions. Exhaust streams from
copper dryers are vented to either a baghouse or an electro-
static precipitator (ESP) to reduce PM emissions. Id. at
19,593. Smelting furnaces vent primary exhaust gases to
adjacent sulfuric acid plants that remove PM by routing the
gas stream first through an ESP and then through a wet
scrubber. Id. at 19,594. Two of the smelters involved in this
rulemaking operate slag cleaning vessels, venting the exhaust
gases to wet scrubbers to reduce PM emissions. Id. at
19,595. Batch converters route emissions to adjacent plants,
baghouses, and ESPs for PM control. Id. at 19,597.
After surveying the technology used at the various loca-
tions, EPA determined that copper smelters used PM control
devices to reduce HAP emissions. EPA accordingly set
standards for HAP emissions in terms of PM, rather than
setting individual limits for each HAP. Because the control
devices operate by reducing PM as a whole, EPA set numeri-
cal limits in terms of PM for each type of primary gas stream.
To control fugitive emissions, EPA set an opacity-based stan-
dard — a standard that limited emissions by measuring the
amount of light passing through emissions vented from cer-
tain smelter exhaust points other than a primary exhaust
stack. The idea was that HAPs contained in process emis-
sions would be regulated through limits on PM, while fugitive
HAPs — the ones that ‘‘leaked out’’ through ceiling exhaust
fans and the like — would be regulated through opacity-based
limits, which would also help ensure that emissions went
through the control devices. EPA’s Final Rule also mandat-
8
ed the use of parameter monitoring to ensure the proper
functioning of the required PM control devices. Such moni-
toring tests whether PM control devices operate as they are
supposed to under a specific parameter previously deter-
mined to ensure compliance with emission standards. EPA
estimated that the regulatory regime set forth in its Final
Rule would reduce HAP emissions from copper smelters
nationwide by 23 percent. Final Rule, 67 Fed. Reg. at 40,478.
Sierra Club did not comment on the proposed emission
standards, and none of the entities that did have challenged
the Final Rule. Sierra Club nonetheless challenges the Final
Rule on several grounds: (1) EPA’s MACT determination is
unlawful and arbitrary and capricious; (2) EPA’s decision to
use PM as a surrogate for HAPs is not reasonable; (3) EPA
failed adequately to explain its decision to use PM as a
surrogate; and (4) the opacity-based standard is not a proper
emission standard. Sierra Club also challenges EPA’s refusal
to impose beyond-the-floor limits and the agency’s alleged
failure to take into account non-air quality health and envi-
ronmental impacts. In addition, Sierra Club challenges the
monitoring requirement as inadequate and claims that EPA
violated the Endangered Species Act by issuing the Final
Rule without undertaking the inter-agency consultations re-
quired by that Act.
II. Challenges to EPA’s MACT Determinations
A. PM as a Surrogate
In National Lime, this court confirmed that ‘‘EPA may use
a surrogate to regulate pollutants if it is ‘reasonable’ to do
so.’’ 233 F.3d at 637. Sierra Club does not dispute this
proposition as a general matter, see Reply Br. at 4 n.2, but
raises two broad objections to the use of PM as a surrogate
for HAPs in this particular rulemaking. First, Sierra Club
contends that EPA has set standards on the basis of what PM
control can achieve, violating the statutory requirement that
the minimum standards be based on what the best perform-
ing sources actually achieve. Second, Sierra Club contends
that using PM as a surrogate is not ‘‘reasonable’’ under the
9
criteria set forth in National Lime. We address each conten-
tion in turn.
1. Lawfulness of PM as a Surrogate
During the notice-and-comment period, EPA responded to
an objection to the use of PM as a surrogate by stating that
the CAA ‘‘does not prohibit us from using an appropriate
surrogate pollutant for individual HAP species to confirm the
proper use of MACT.’’ EPA, National Emission Standards
for Hazardous Air Pollutants (NESHAP) for Primary Copper
Smelters — Background Information for Promulgated Stan-
dards 2-2 (2001) (EPA Background Document). Sierra Club
seizes upon that explanation to argue that EPA has violated
Section 7412(d)(3) by setting surrogate emission standards to
confirm the proper use of a chosen technology, instead of
basing standards on what the best sources achieve with
respect to HAP emissions control. Reply Br. at 2. Sierra
Club contends that copper smelters achieve HAP emission
reductions not just through PM control, but by altering ore
inputs as well. Because EPA promulgated the emission
standards based only on PM control without considering ore
inputs, Sierra Club argues, the standards fail to reflect what
the best-performing sources achieve: ‘‘setting standards TTT
that reflect only what is achievable through the use of a
particular control technology contravenes the Act.’’ Id.
Sierra Club relies heavily on this court’s decision in CKRC,
but EPA avoided the problems that infected its analysis in
that case. The statute requires EPA to set minimum emis-
sion standards at the level achieved by the best-performing
sources. See 42 U.S.C. § 7412(d)(3). In CKRC, EPA estab-
lished a ‘‘MACT pool’’ comprised of the best-performing
sources, ‘‘identified the primary emission control technology
used by the sources in the MACT pool,’’ selected that technol-
ogy as the ‘‘MACT control,’’ and set the final emission
standard at the level of the worst-achieving source using the
MACT control. 255 F.3d at 859 (emphasis added). EPA
defended that approach as a means of ensuring achievability,
10
arguing that Section 7412(d)(3) imported Section 7412(d)(2)’s
achievability standard. We disagreed. Id. at 861.
EPA advanced an alternative argument, to the effect that
adopting emission standards based on what the worst-
achieving sources using MACT achieved did reflect what the
best-achieving sources actually achieved. See id. at 862. We
were having none of that: The worst-performing sources
using MACT technology could not be representative of the
best-performing sources, because evidence showed that (1)
some of the best-performing sources used other control de-
vices in combination with the MACT technology, (2) the
performance of different models of the same technology
varied based on certain features, and (3) other factors such as
feed rate and material composition affected emission outputs.
Id. at 862–64.
The instant case is quite different. EPA did not violate
Section 7412(d)(3) by setting emission standards based on the
worst-performing sources using MACT. Nor did EPA use
the worst-performing sources to estimate the performance of
the best-performing sources. Sierra Club challenges only the
type of emission standard — PM as a surrogate for HAPs —
not, as in CKRC, the numerical limitation set by the standard.
In this case, EPA promulgated standards that accurately
reflect the control achieved by the best-performing sources.
EPA established emission standards for the various copper
smelting processes based upon the actual PM emissions of the
relevant units from performance tests, e.g., Final Rule, 67
Fed. Reg. at 40,482–83 (smelting process emissions, batch
converters, slag cleaning vessels), or based upon established
regulatory limits, e.g., Proposed Rule, 63 Fed. Reg. at 19,593–
94; EPA Background Document, at 2-10–2-11 (copper con-
centrate dryers). Contrary to Sierra Club’s assertion that
EPA established an equipment standard, EPA started down
that road but pulled back:
After careful review and evaluation of comments re-
ceived objecting to our use of an equipment standard
rather than a numerical emission limit and new emissions
data obtained since proposal, we concluded that a change
11
in the proposed standards for process off-gas emissions
was warranted. As a result, we issued a supplement to
the proposed rule TTT in which we proposed a numerical
emission standard that would limit the concentration of
total particulate matter in the off-gases discharged.
Final Rule, 67 Fed. Reg. at 40,482/3 (referring to emission
standards for smelting furnaces, slag cleaning vessels, and
batch converters and citing National Emissions Standards for
Hazardous Air Pollutants for Source Categories: National
Emissions Standards for Primary Copper Smelters, 65 Fed.
Reg. 39,326 (June 26, 2000) (Supplement)). EPA complied
with Section 7412(d)(3) by setting emission limits on the basis
of the PM control that the best sources actually achieved, not
on the basis of what any source using PM control achieved.
EPA did not repeat its CKRC missteps. We now turn to
Sierra Club’s contention that use of PM as a surrogate for
metal HAPs was unreasonable under National Lime.
2. Reasonableness of PM as a Surrogate
In National Lime, this court established a three-part anal-
ysis for determining whether the use of PM as a surrogate
for HAPs is reasonable: PM is a reasonable surrogate for
HAPs if (1) ‘‘HAP metals are invariably present in TTT PM;’’
(2) ‘‘PM control technology indiscriminately captures HAP
metals along with other particulates;’’ and (3) ‘‘PM control is
the only means by which facilities ‘achieve’ reductions in HAP
metal emissions.’’ 233 F.3d at 639. If these criteria are
satisfied and the PM emission standards reflect what the best
sources achieve — complying with Section 7412(d)(3) —
‘‘EPA is under no obligation to achieve a particular numerical
reduction in HAP metal emissions.’’ Id.
The use of PM as a surrogate in this case is reasonable.
First, it is undisputed that HAPs are invariably present in
PM. Second, EPA determined that the PM control technolo-
gies used by primary copper smelters inevitably removed
HAPs as part of PM. See Proposed Rule, 63 Fed. Reg. at
19,592/3 (‘‘The control technologies used for the control of PM
12
emissions achieve equivalent levels of performance on metallic
HAP emissions.’’). There is some dispute, however, whether
copper smelters use other control technologies besides PM
control to limit HAPs.
Sierra Club claims that the record shows that two copper
smelters use ore-switching to control PM. A 1995 EPA
report cites 1992 impurity data to conclude that the Phelps
Dodge–Chino smelter had ‘‘no control of secondary hood or
matte and slag tapping gases’’ but ‘‘achieves low HAP emis-
sions through low-input-impurity feeds.’’ EPA, A-96-22 No.
II-A-1, Final Summary Report: Primary Copper Smelters
National Emission Standard for Hazardous Air Pollutants 5
(July 1995) (Final Report). The report further stated that
the ‘‘Phelps Dodge–Hidalgo smelter also has very low levels
of HAPs in ore concentrate feedsTTTT’’ Id.
The record, however, shows that between the 1995 report
and the proposed rulemaking, both of these smelters installed
PM controls to regulate their emissions. In 1996, the Hidal-
go smelter installed a baghouse to control matte and slag
tapping hood emissions. EPA, A-96-22 No. II-E-8, File
Memorandum from E. Crumpler, Office of Air Quality Plan-
ning and Standards (July 28, 1997). During EPA emissions
testing at the Chino smelter in April 1997, EPA reported that
the smelter used a secondary hood system to route off-gases
to a baghouse prior to discharge to the atmosphere. EPA A-
96-22 No. II-I-2, Emissions Test Report: Primary Copper
Smelter Converter Aisle Fugitive Emissions; Phelps Dodge
Hurley, New Mexico ¶ 2.1 (Chino smelter). When it came
time to address the instant question, EPA consequently found
that PM control was the only control technology used by the
industry. See Proposed Rule, 63 Fed. Reg. at 19,585/3. We
have no basis for rejecting that finding as arbitrary or
capricious. See Ethyl Corp. v. EPA, 51 F.3d 1053, 1064 (D.C.
Cir. 1995) (‘‘If EPA acted within its delegated statutory
authority, considered all of the relevant factors, and demon-
strated a reasonable connection between the facts on the
record and its decision, we will uphold its determination.’’).
13
Sierra Club uses National Lime’s statement that ‘‘EPA
must consider the potential impact upon emissions of changes
in inputs,’’ 233 F.3d at 639, as a basis to argue that ‘‘PM is
not a reasonable surrogate where other factors (in the instant
case, the HAP content of the ore used) affect HAP metal
emissions.’’ Reply Br. at 5. The requirement in National
Lime was that other inputs must ‘‘affect HAP metal emis-
sions in the same fashion that they affect the other compo-
nents of PM.’’ 233 F.3d at 639. Put another way, ‘‘PM
might not be an appropriate surrogate for HAP metals if
switching fuels would decrease HAP metal emissions without
causing a corresponding reduction in total PM emissions.’’
Id. The reason is clear: if EPA looks only to PM, but HAPs
are reduced by altering inputs in a way that does not reduce
PM, the best achieving sources, and what they can achieve
with respect to HAPs, might not be properly identified.
Nothing in the record, however, supports the proposition
that switching to cleaner ore will decrease HAPs without a
reduction in PM. HAP metals are a component of PM, see
Proposed Rule, 63 Fed. Reg. at 19,585/1 (‘‘metallic impurities
in the copper ore can be released into the atmosphere in the
form of particulate matter (PM) during certain smelting
operations’’), so any reduction in HAPs would in turn reduce
PM. As EPA explained:
During the smelting process TTT HAP metal species
either are eliminated in the molten slag tapped from the
process vessels or are vaporized and discharged in the
process vessel off-gases. Upon cooling of the process
off-gases, the volatilized HAP metal species condense,
form aerosols, and behave as particulate matter. TTT An
emission characteristic common to all primary copper
smelters and similar source categories is the fact that the
metal HAP are a component of the particulate matter
contained in the process off-gases discharged from smelt-
ing and converting operations.
Supplement, 65 Fed Reg. at 39,329/1–2 (emphases added);
see EPA Background Document, at 3-2 (‘‘metal HAP emis-
sions from copper converters behave as particulate matter’’).
14
Sierra Club argues that the use of PM as a surrogate is not
reasonable because the HAP content of PM will vary accord-
ing to the feedrate. But as we explained in National Lime,
‘‘even if the ratio of metals to PM is small and variable, or
simply unknown, PM is a reasonable surrogate for the met-
als — assuming TTT that PM control technology indiscrimi-
nately captures HAP metals along with other particulates.’’
233 F.3d at 639 (emphasis added). On the record before us,
EPA concluded that ‘‘[s]trong direct correlations exist be-
tween the emissions of total particulate matter and metal
HAP compounds. Emission limits established to achieve
good control of total particulate matter will also achieve good
control of metal HAP.’’ Supplement, 65 Fed. Reg. at
39,329/1–2. As EPA explained, ‘‘[t]he control technologies
used for the control of PM emissions achieve equivalent levels
of performance on metallic HAP emissions.’’ Proposed Rule,
63 Fed. Reg. at 19,592/3. On this record, the use of PM as a
surrogate is reasonable, even in light of the potential variabil-
ity of impurities in copper ore.
B. EPA’s Consideration of Alternatives to the PM Stan-
dard
Sierra Club argues that using PM as a surrogate is arbi-
trary and capricious in light of standards promulgated for
other industries, under which PM was not similarly used as a
surrogate. Sierra Club directs the court to EPA’s failure to
explain (1) why PM was a proper surrogate for HAP metals
here when it was not in the hazardous waste combustor
(HWC) rulemaking, and (2) why EPA did not use other
surrogates, as, for example, it used lead as a surrogate in the
secondary lead smelter rulemaking. Pet. Br. at 29.
Without specific reference to the HWC and secondary lead
smelter regulations, EPA reasonably articulated its decision
to use PM as a surrogate in response to public comments.
EPA explained that a surrogate was needed in light of the
impracticality of setting individual standards for each metal,
due to the variability of HAPs in copper ore stocks:
15
Th[e] inherent variability and unpredictability of the
metal HAP compositions and amounts in copper ore
concentrates affect the composition and amount of HAP
metals in the process off-gas emissions. As a result,
prescribing individual numerical emission limits for each
HAP species (e.g., a specific emission limit for arsenic, a
specific emission limit for lead, etc.) is impracticable, if
not impossible, to do.
Given that prescribing individual numerical emission
limits for HAP metal is not a practicable approach in this
case, an alternative approach is to use particulate matter
as a surrogate pollutant for the metal HAP emitted from
primary copper smelters.
EPA Background Document, at 2-2–2-3.
EPA then explained its decision to use PM as the surro-
gate:
— ‘‘metal HAP compounds are a component of the [PM]
contained in the process off-gases,’’
— ‘‘[s]trong direct correlations exist between the emis-
sions of [PM] and metal HAP compounds,’’ and
— ‘‘[e]mission limits established to achieve good control
of [PM] will also achieve good control of metal HAP.’’
Id. at 2-3.
Based on this response to public comments, we conclude
that EPA adequately considered alternatives to the PM stan-
dard. EPA was not required to give an affirmative justifica-
tion for differences with regulations governing other indus-
tries. ‘‘The failure to respond to comments is significant only
insofar as it demonstrates that the agency’s decision was not
based on a consideration of the relevant factors.’’ Thompson
v. Clark, 741 F.2d 401, 409 (D.C. Cir. 1984) (internal quotation
marks and citation omitted); accord American Iron & Steel
Inst. v. EPA, 115 F.3d 979, 1005 (D.C. Cir. 1997) (finding
comment response sufficient if it ‘‘demonstrates that the
agency considered the ‘relevant factors’ raised by the sug-
gested alternatives’’); Texas Mun. Power Agency v. EPA, 89
16
F.3d 858, 876 (D.C. Cir. 1996). EPA’s explanation makes it
evident that it did consider the relevant factors.
This court has adopted an ‘‘every tub on its own bottom’’
approach to EPA’s setting of standards pursuant to the CAA,
under which the adequacy of the underlying justification
offered by the agency is the pertinent factor — not what the
agency did on a different record concerning a different indus-
try. See Portland Cement Ass’n v. Ruckelshaus, 486 F.2d
375, 389 (D.C. Cir. 1973). The question of whether EPA
reasonably considered alternatives ‘‘can typically be decided
on the basis of information concerning that industry alone.’’
Id. The record in this case demonstrates that EPA reason-
ably explained its decision based on the specifics of primary
copper smelters. EPA could have noted where the bases for
its decision in this case differed from those with respect to
other decisions in other cases, as was done in EPA’s brief to
this court, see, e.g., Resp. Br. at 23 (PM control inadequate in
the HWC context because feedrate control was also used to
reduce HAP emissions, unlike in copper smelter context), but
such explanations are not required given the different con-
texts of the various rulemakings. See Portland Cement, 486
F.2d at 389 (‘‘the Administrator is not required to present
affirmative justifications for different standards in different
industries’’); National Lime Ass’n v. EPA, 627 F.2d 416, 447
n.108 (D.C. Cir. 1980) (‘‘That different industries may be
subject to different standards and that the Administrator
need not bear the burden of explaining those differences is
clear.’’).
C. Opacity-Based Emission Standard
During the copper smelting process, some HAP emissions
evade the capture systems and are released into the atmo-
sphere through roof-top vents spanning the length of the
converter building or through exhaust fans. EPA addressed
these emissions — the ‘‘fugitive’’ HAP emissions — by impos-
ing a four percent opacity limit at building vents. Sierra
Club objects that (1) opacity is not a surrogate for HAPs, and
therefore EPA has failed to establish an emission standard
for roof vents and exhaust fans, and (2) the opacity standard
17
cannot be defended as a work practice or operational stan-
dard under 42 U.S.C. § 7412(h)(1), because EPA has failed to
meet the statutory prerequisites for imposing such a standard
in lieu of an emission standard.
EPA’s decision to use an opacity-based standard for fugi-
tive HAP emissions is reasonable. Sierra Club focuses on a
portion of EPA’s response to public comment on the opacity-
based standard — ‘‘we are using the opacity TTT as an
indicator of converter capture system performance,’’ EPA
Background Document, at 3-1 — to argue that EPA itself
regarded the opacity limit as an operational standard, not an
emission standard. Reading the entirety of the response,
EPA’s reasoning is clear:
Given that opacity is an indicator of the level of particu-
late matter emitted, designing and operating a copper
converter capture system to minimize the visible emis-
sions from the building will increase the amount of
particulate matter captured and vented to a control
device. Given that metal HAP emissions from copper
converters behave as particulate matter, increasing the
level of particulate matter emissions control will increase
the level of metal HAP emissions control.
Id. at 3-2. Opacity measures PM and limiting PM reduces
HAP emissions. In addition, limiting fugitive HAP emissions
through opacity-based standards further controls HAP emis-
sions by ensuring that the converter capture system is work-
ing well enough to make the PM standard meaningful —
there is no sense focusing on the primary exhaust streams if
most of the emissions go out the roof. See id. at 3-1. We
have already accepted EPA’s contention in another case, in
response to an objection by Sierra Club, that ‘‘opacity moni-
toring promotes good operation and maintenance, which in
turn reasonably ensure compliance with the PM standard.’’
National Lime, 233 F.3d at 635. We have no reason to
question it here.
EPA established the opacity-based standard according to
the approach mandated by statute, basing it ‘‘on the average
of the test data for the five best performing sources.’’ Final
18
Rule, 67 Fed. Reg. at 40,485. EPA’s opacity-based standard
is an emission standard that is accordingly both reasonable
and lawful.
III. Challenges to Final Standards
A. EPA’s Rejection of Beyond-the-Floor Standards
The CAA requires — as a second step in the technology-
based analysis — that EPA consider whether beyond-the-
floor standards are necessary under Section 7412(d)(2) to
augment the minimum standard set under Section 7412(d)(3).
When considering whether to implement any such additional
measures, EPA must ‘‘tak[e] into consideration the cost of
achieving such emission reduction, and any non-air quality
health and environmental impacts and energy requirements.’’
42 U.S.C. § 7412(d)(2).
1. Sierra Club challenges EPA’s rejection of ore selection
as a basis for imposing a beyond-the-floor standard. It
argues that EPA should require primary copper smelters to
use cleaner copper ore in order to achieve ‘‘the maximum
degree of reduction in HAPs’’ under Section 7412(d)(2). Pet.
Br. at 32. EPA argued that it properly rejected ore-
switching as a beyond-the-floor measure because (1) it is not
permitted to consider ore-switching as a control strategy, and
(2) substitution of cleaner ore stocks is not feasible. Resp.
Br. at 28–29.
The CAA specifically includes ‘‘substitution of materials’’ as
one of the means of reducing pollution, 42 U.S.C.
§ 7412(d)(2)(A), lending support to Sierra Club’s view that
EPA should have considered ore-switching. Legislative his-
tory, however, may be consulted to ‘‘shed new light on
congressional intent, notwithstanding statutory language that
appears superficially clear.’’ National Rifle Ass’n v. Reno,
216 F.3d 122, 127 (D.C. Cir. 2000) (internal quotation marks
omitted). EPA directs the court to the 1990 Amendments
‘‘Conference Committee Report’’ to support its contention
19
that it is not permitted to consider ore-switching. See Resp.
Br. at 28.1 The Joint Explanatory Statement provides:
For categories and subcategories of sources of [HAPs]
engaged in mining, extraction, beneficiation, and process-
ing of nonferrous ores, concentrates, minerals, metals,
and related in-process materials, the Administrator shall
not consider the substitution of, or other changes in,
metal- or mineral-bearing raw materials that are used as
feedstocks or material inputs TTT in setting emission
standards, work practice standards, operating standards
or other prohibitions or requirements or limitations un-
der this section for such categories and subcategories.
Joint Explanatory Statement of the Committee of Confer-
ence, H.R. Rep. No. 101-952, at 339 (1990).
We need not resolve the statutory question, however, be-
cause EPA explained that the substitution of cleaner ore
stocks was not, in any event, a feasible basis on which to set
emission standards. Metallic impurity levels are variable and
unpredictable both from mine to mine and within specific ore
deposits, Proposed Rule, 63 Fed. Reg. at 19,592/2–3, thereby
precluding ore-switching as a predictable and consistent con-
trol strategy. EPA also determined that ‘‘there are no
commercial-scale pretreatment processes available for remov-
ing or reducing the metallic HAP contained in the copper
concentrate.’’ Id. at 19,601. We conclude that EPA reason-
ably refused to set beyond-the-floor standards that were
based on a requirement that smelters switch ore supplies.
2. Sierra Club also challenges EPA’s refusal to set be-
yond-the-floor PM limits for fugitive HAP emissions at the
1986 national emission standard for HAPs (NESHAP) level
1 EPA actually cites to the ‘‘Joint Explanatory Statement’’ that
accompanied the Conference Committee Report. The Joint Ex-
planatory Statement describes how the differences between the
Senate and House were resolved in the Conference Committee.
See Roeder v. Islamic Republic of Iran, 333 F.3d 228, 236 (D.C. Cir.
2003). The Joint Explanatory Statement may be helpful in deter-
mining Congress’s intent, but does not carry the same weight as the
Conference Committee Report itself. See id. at 236–37.
20
for copper smelters. According to Sierra Club, EPA’s refusal
was arbitrary and capricious, because the 1986 NESHAP is
‘‘an achievable standard’’ under Section 7412(d)(2). See Pet.
Br. at 33.
The 1986 NESHAP level reflects emission standards pro-
mulgated under a risk-based methodology — the methodolo-
gy used prior to the 1990 Amendments’ switch to technology-
based standards. The CAA now requires that beyond-the-
floor standards be achievable and provides a framework for
analyzing achievability, including consideration of cost, energy
requirements, and other factors. 42 U.S.C. § 7412(d)(2).
The 1986 NESHAP standard did not go through that process.
When the 1986 NESHAP standard was proposed, only one
smelter was actually subject to it, and that smelter ceased
operations in 1985, before the standard took effect. National
Emissions Standards for Hazardous Air Pollutants: Stan-
dards for Inorganic Arsenic, 51 Fed. Reg. 27,956, 27,957 (Aug.
4, 1986) (codified at 40 C.F.R. pt. 61).2 EPA acted reasonably
in not adopting a beyond-the-floor standard promulgated
under a totally different risk-based regime with very limited
evidence of achievability.
3. Sierra Club also argues that the final regulation is
arbitrary and capricious because EPA failed to respond to a
commenter’s contention that a beyond-the-floor standard of
23 mg/dscm should be set for copper concentrate dryers.
The commenter argued that ‘‘one state air permit limits dryer
PM emissions to 23 mg/dscm,’’ so the limit was ‘‘evidently
achievable.’’ Arizona Center for Law in the Public Interest,
A-96-22 Item No. IV-D-8, Comments on Proposed National
Emissions Standards for Primary Copper Smelters 7 (July
20, 1998). EPA specifically noted the commenter’s conten-
tion. EPA Background Document, at 2-9. Indeed, EPA
factored the 23 mg/dscm limit in to its determination of the 50
2 The emission standard provided by the 1986 NESHAP only
applies if specific arsenic feed rates are exceeded. 40 C.F.R.
§ 61.172. No existing copper smelters reach that threshold and
none are subject to that standard. Proposed Rule, 63 Fed. Reg. at
19,586.
21
mg/dscm limit achieved by the five best-performing sources.
Id. at 2-11. EPA then went on to explain that ‘‘there are no
reasonable alternatives beyond the MACT floor for control of
process particulate emissions from existing copper concen-
trate dryers.’’ Id. Simply asserting, as the commenter did,
that the state permit limit was ‘‘evidently achievable’’ did not
compel any additional rejoinder from EPA. As we recently
explained in rejecting another effort to fault EPA for not
considering beyond-the-floor measures:
There TTT doesn’t appear to be any evidence in the
record about the costs of the pollution prevention mea-
sures the Sierra Club advocates. In the absence of any
type of quantification of benefits or costs, the Adminis-
trator had no basis for finding that, ‘‘taking into account
the cost,’’ emissions reductions from pollution prevention
programs were ‘‘achievable’’ as the statute uses the word.
Sierra Club, 167 F.3d at 666. Accordingly, we reject Sierra
Club’s challenge to the adequacy of EPA’s response to this
particular comment.
B. Non-Air Quality Environmental Effects
Sierra Club alleges that EPA refused to consider ‘‘non-air
quality health and environmental impacts,’’ as required under
Section 7412(d)(2). Sierra Club interprets this provision to
require EPA to consider the ‘‘impacts of deposition, persis-
tence, toxicity and bioaccumulation of metal HAP emissions
on people, wildlife and the environment.’’ Pet. Br. at 36. In
other words, ‘‘non-air quality TTT impacts’’ are just like air
quality impacts, except that the impact is not delivered direct-
ly through the air but instead, for example, by ‘‘deposition’’ —
the eventual settling of HAPs on the ground. EPA takes a
different view — that ‘‘ ‘non-air quality TTT impacts’ refers to
any health and environmental impacts TTT that may result
directly or indirectly from measures that will achieve the
emission reductions.’’ Resp. Br. at 31. In other words, ‘‘non-
air quality TTT impacts’’ are those that result from the
required efforts to control the air quality impacts of the
underlying manufacturing process.
22
Congress did not define ‘‘non-air quality TTT impacts,’’ so
we will defer to EPA’s construction of the ambiguous statuto-
ry language, so long as it is reasonable. Chevron U.S.A., Inc.
v. NRDC, 467 U.S. 837, 842–43 (1984). It is. The statute
groups consideration of ‘‘non-air quality TTT impacts’’ with
consideration of ‘‘the cost of achieving such emission reduc-
tion’’ and ‘‘energy requirements.’’ 42 U.S.C. § 7412(d)(2).
This context strongly supports EPA’s interpretation of ‘‘non-
air quality TTT impacts’’ to mean the by-products of the
control technology — just as additional cost or energy needs
are by-products of controlling air quality impacts. See Wash-
ington State Dep’t of Soc. & Health Servs. v. Guardianship
Estate of Keffeler, 537 U.S. 371, 384–85 (2003).
Second, there is no apparent reason to suppose that Con-
gress would have required immediate consideration of health
and environmental impacts caused by, say, deposition of
HAPs, while postponing consideration of the more direct
health and environmental impacts caused by emission of
HAPs into the air until the second stage of standard promul-
gation under the CAA. As discussed, the 1990 Amendments
established a two-phase approach to promulgating emission
standards. The first phase — at issue in this case —
requires a technology-based approach. See 42 U.S.C.
§ 7412(d). The second phase occurs eight years later and
involves a risk-based approach. See id. § 7412(f)(2)(A)
(‘‘Emissions standards promulgated under this subsection
shall provide an ample margin of safety to protect public
healthTTTT’’). That risk-based analysis requires EPA to con-
sider, inter alia, public health and adverse environmental
effects, id. — precisely what Sierra Club contends EPA must
consider now with respect to non-air quality impacts. Sierra
Club’s interpretation would collapse the technology-
based/risk-based distinction at the heart of the Act, under-
mining the central purpose of the 1990 Amendments — to
facilitate the near-term implementation of emission standards
through technology-based solutions. In doing so, that inter-
pretation would reintroduce the very problem Congress
sought to exorcize — that the pursuit of the perfect (risk-
23
based standards) had defeated timely achievement of the
good (technology-based standards). EPA’s reading of the
statute is reasonable.
IV. Monitoring
EPA’s monitoring requirements must ‘‘provide a reason-
able assurance of compliance with emissions standards.’’
Natural Res. Def. Council, Inc. v. EPA, 194 F.3d 130, 136
(D.C. Cir. 1999) (NRDC). Sierra Club argues that the par-
ameter monitoring required by EPA can provide such assur-
ance only if the monitored control device is the only factor
affecting emissions — in contrast to this case, where
strength, temperature, and content of gas streams allegedly
also affect emissions. Pet. Br. at 43. That argument is
waived because it was not raised below: the record sections
cited by Sierra Club in its brief, see id., refer only to pre-
proposal letters — not public comments on the Proposed
Rule — and are therefore inadequate to preserve the argu-
ment for consideration here. See 42 U.S.C. § 7607(d)(7)(B)
(‘‘Only an objection to a rule or procedure which was raised
TTT during the period for public comment TTT may be raised
during judicial review.’’).
Sierra Club also argues that EPA’s failure to require
continuous monitoring violates Section 7414(a)(3), which pro-
vides that EPA, with respect to major stationary sources —
and copper smelters are certainly those — ‘‘shall TTT require
enhanced monitoring.’’ Id. § 7414(a)(3). But the CAA itself
provides that ‘‘continuous emissions monitoring need not be
required if alternative methods are available that provide
sufficiently reliable and timely information for determining
compliance,’’ id. § 7661c(b), and this court has already reject-
ed claims that Section 7414(a)(3) requires continuous monitor-
ing. See NRDC, 194 F.3d at 135 (‘‘Nothing in the phrase
‘enhanced monitoring’ supports [the] view that only continu-
ous or direct emissions monitoring can be regarded as ‘en-
hanced’TTTT’’).
To ensure ‘‘sufficiently reliable and timely information for
determining compliance,’’ EPA imposed monitoring require-
ments in this case: smelters must (1) demonstrate initial
24
compliance through performance testing, proving achieve-
ment of emission standards; (2) continuously monitor operat-
ing parameters, and show that the facility operates within
those parameters; (3) repeat performance tests at least annu-
ally; (4) comply with inspection and maintenance require-
ments for the control devices; and (5) maintain monitoring
data and submit compliance reports. See 40 C.F.R.
§§ 63.1450–.1455. EPA determined that such a regime of
parameter monitoring would assure compliance with the stan-
dards it was imposing. ‘‘[B]ecause analysis of this issue
requires a high level of technical expertise, we must defer to
the informed discretion of the Agency.’’ National Lime, 233
F.3d at 635 (internal quotation marks omitted).
Sierra Club also objects that EPA failed to explain ade-
quately its decision not to require continuous emissions moni-
toring (CEMS) or continuous opacity monitoring (COMS) in
light of its usual preference for continuous monitoring. As
noted, EPA has broad discretion in selecting a monitoring
regime that ensures compliance. See id. There is no pre-
sumption in favor of any particular type of monitoring, see
NRDC, 194 F.3d at 136–37, and EPA has imposed different
monitoring requirements in different situations. EPA rea-
sonably articulated the basis for its decision, explaining that
‘‘we are using control device operating parameter monitoring
to verify that the control device continues to operate at the
same set of conditions as the device was operating when the
required emissions testing was performed to demonstrate
compliance with the applicable limit.’’ EPA Background Doc-
ument, at 5-4. The use of parameter monitoring verifies
compliance with the required standard by showing that the
control device continues to operate at the level achieved
during emissions testing. We have no basis for second-
guessing EPA’s judgment that the regime it imposed would
meet the statutory standard of ‘‘sufficiently reliable and time-
ly information for determining compliance.’’ 42 U.S.C.
§ 7661c(b); see Consumer Elec. Ass’n v. FCC, 347 F.3d 291,
304 (D.C. Cir. 2003) (‘‘We will not TTT second-guess the
[agency’s] weighing of costs and benefits.’’).
25
V. Endangered Species Act
Finally, Sierra Club claims that EPA violated the Endan-
gered Species Act (ESA), 16 U.S.C. §§ 1531–1544. Noting
that the ESA requires government agencies to consult with
the Fish and Wildlife Service (FWS) and the National Marine
Fisheries Service (NMFS) before taking action that could
affect endangered species, see id. § 1536(a)(2), Sierra Club
argues that EPA should have consulted FWS and NMFS
before promulgating the primary copper smelter emission
regulations.
As explained above, the CAA requires EPA to undertake a
two-phase process for promulgating regulations to reduce
HAP emissions. EPA considers ‘‘adverse environmental ef-
fect[s]’’ only during the second, risk-based phase. 42 U.S.C.
§ 7412(f)(2)(A). The statute specifically defines the term
‘‘adverse environmental effect’’ to include ‘‘any significant and
widespread adverse effect, which may reasonably be antici-
pated, TTT on populations of endangered or threatened spe-
cies.’’ Id. § 7412(a)(7).
Congress, therefore, expressly channeled consideration of
endangered species to the second phase of CAA standard
promulgation. The rulemaking in this case involves the first
phase. Once again, Sierra Club would collapse the separate
technology-based/risk-based phases of the statute into a sin-
gle analysis. We reject that effort, which would undo what
the 1990 Amendments sought to accomplish. EPA’s determi-
nation to postpone consultation under the ESA to the second
stage of regulation under the CAA was a reasonable one and
not contrary to law.
* * *
The petition for review is denied.