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United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued September 15, 2003 Decided April 9, 2004
No. 02-1181
STATE OF WEST VIRGINIA,
PETITIONER
v.
ENVIRONMENTAL PROTECTION AGENCY,
RESPONDENT
STATE OF NEW YORK, ET AL.,
INTERVENORS
Consolidated with
02-1185, 02-1188, 02-1193, 02-1200, 02-1204, 02-1205
On Petitions for Review of an Order of the
Environmental Protection Agency
Mary E. Welsh, Assistant Attorney General, Illinois Attor-
ney General’s Office, argued the cause for petitioners State of
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
Illinois and West Virginia. With her on the briefs were Lisa
Madigan, Attorney General, Gary S. Feinerman, Solicitor
General, and Thomas H. Zerbe, Senior Counsel, West Virgi-
nia Attorney General’s Office.
Norman W. Fichthorn argued the cause for petitioners
Utility Air Regulatory Group, et al. on Common Issues.
With him on the briefs were David M. Flannery, Gale R.
Lea, Kathy G. Beckett, Mel S. Schulze, Steven G. McKinney,
C. Grady Moore, III, Philip S. Gidiere, III, Daniel S. Rein-
hardt, Margaret C. Campbell, and Gary R. Sheehan, Jr.
Andrea B. Field entered an appearance.
C. Grady Moore, III, argued the cause for petitioners
Alabama Power Company, et al. on State–Specific Issues
With him on the briefs were Steven G. McKinney, P. Stephen
Gidiere, III, Daniel S. Reinhardt, Margaret Claiborne
Campbell, Gary R. Sheehan, Jr., David M. Flannery, Gale R.
Lea, and Kathy G. Beckett.
Norman L. Rave, Jr., Attorney, U.S. Department of Jus-
tice, argued the cause for respondent. With him on the brief
were Howard J. Hoffman and Dwight C. Alpern, Attorneys,
Environmental Protection Agency.
William L. Pardee, Assistant Attorney General, Common-
wealth of Massachusetts Attorney General’s Office, argued
the cause for intervenors States of Massachusetts, et al.
With him on the brief were Thomas F. Reilly, Attorney
General, Richard Blumenthal, Attorney General, Connecticut
Attorney General’s Office, Eliot Spitzer, Attorney General,
New York State Attorney General’s Office, J. Jared Snyder,
Assistant Attorney General, G. Steven Rowe, Attorney Gener-
al, Maine Attorney General’s Office, Gerald D. Reid, Assis-
tant Attorney General, J. Joseph Curran, Jr., Attorney Gen-
eral, Maryland Attorney General’s Office, Kathy M. Kinsey,
Assistant Attorney General, Peter C. Harvey, Attorney Gen-
eral, New Jersey Attorney General’s Office, Howard Dedul-
dig, Deputy Attorney General, Patrick C. Lynch, Attorney
General, Rhode Island Attorney General’s Office, Tricia Je-
3
dele, Special Assistant Attorney General, Peter W. Heed,
Attorney General, New Hampshire Attorney General’s Office,
Maureen D. Smith, Senior Assistant Attorney General, Kris-
ten Campfield, William H. Sorrell, Attorney General, Ver-
mont Attorney General’s Office, Eric Titrud, Assistant Attor-
ney General, and Kevin Leske, Special Assistant Attorney
General. John M. Looney, Jr., Assistant Attorney General,
Connecticut Attorney General’s Office, entered an appear-
ance.
Before: GINSBURG, Chief Judge, and SENTELLE and ROGERS,
Circuit Judges.
Opinion for the Court filed by Circuit Judge SENTELLE.
SENTELLE, Circuit Judge: This is a petition for review of
the Environmental Protection Agency’s (‘‘EPA’’ or ‘‘Agency’’)
response to this Court’s remands in Appalachian Power Co.
v. EPA, 249 F.3d 1032 (D.C. Cir. 2001) (‘‘Appalachian I’’),
and Appalachian Power Co. v. EPA, 251 F.3d 1026 (D.C. Cir.
2001) (‘‘Appalachian II’’). In those cases, we remanded the
EPA’s electric generating unit (‘‘EGU’’) growth-factor deter-
minations, which are used to develop Nitrogen Oxide (‘‘NOx’’)
emission limits for regulated states and EGUs. Petitioners—
two states and several business and energy policy entities—
raise multiple challenges to the Agency’s Order on remand.
Several states intervene in support of the EPA.
We hold that the EPA satisfied its obligation on remand to
engage in reasoned decisionmaking and explain its choice of
methodology. The remaining claims are not properly before
this Court, as they were not raised at the time of the
rulemaking or in the initial proceedings, and the EPA did not
reopen these issues on remand. For these reasons, we deny
the petitions.
I. Background
A. Regulatory Background
The Clean Air Act, 42 U.S.C. § 7401 et seq. (1994) (‘‘CAA’’),
requires the EPA to identify air pollutants that endanger the
public health, and to formulate National Ambient Air Quality
4
Standards (‘‘NAAQS’’) that specify the maximum permissible
concentrations of those pollutants in the ambient air. Once
the EPA has established NAAQS, each state must adopt a
‘‘state implementation plan’’ (‘‘SIP’’) ‘‘providing for the imple-
mentation, maintenance, and enforcement of the NAAQS.’’
Michigan v. EPA, 213 F.3d 663, 669 (D.C. Cir. 2000). Pursu-
ant to the statute, the EPA has promulgated NAAQS for
ozone, which is linked to multiple adverse health effects. See
40 C.F.R. pt. 50 (2003). Ozone, itself, is not emitted directly
into the air; rather, it is formed from chemical reactions
between NOx and volatile organic compounds in the presence
of sunlight. NOx is, therefore, a ‘‘precursor’’ of ozone. NOx
is emitted primarily from fossil fuel combustion sources,
including motor vehicles and power plants. Owing to the
ability of NOx to move through the atmosphere, emissions of
NOx in one area can result in ozone non-attainment in a
distant area. Evidence in the record demonstrates that
states in the eastern United States have difficulty attaining
ozone standards because of ozone, or ozone precursor, emis-
sions in upwind states. 64 Fed. Reg. 28,253 (May 25, 1999).
The two rules at issue in this petition deal with NOx exhaust
limitations on upwind states and EGUs within their borders.
The first rule was based on the work of the Ozone Trans-
port Assessment Group (‘‘OTAG’’). The OTAG was a nation-
al work group comprising 37 states, along with representa-
tives of EPA, industry, and environmental groups, formed ‘‘to
study and devise solutions to the interstate ozone transport
problem.’’ Michigan v. EPA, 213 F.3d at 672; see also 62
Fed. Reg. 60,318 at 60,319. Based on OTAG’s findings, EPA
determined that NOx emissions from 23 jurisdictions were
‘‘contribut[ing] significantly’’ to non-attainment in down-
wind states in violation of the CAA. 42 U.S.C.
§ 7410(a)(2)(D)(i)(I). Accordingly, in October 1998, the EPA
issued the NOx State Implementation Plans Call, which re-
quired 22 states and the District of Columbia to revise their
SIPs to impose controls on NOx emissions. 63 Fed Reg.
57,356 (Oct. 27, 1998) (‘‘NOx SIP Call’’). Under the NOx SIP
Call, each upwind state must limit its summertime NOx
5
emissions to a statewide emissions ‘‘budget.’’ ‘‘The budgets
represent the amount of allowable NOx emissions remaining
after a covered state prohibits the NOx amount contributing
significantly to downwind non-attainment.’’ Michigan v.
EPA, 213 F.3d 663, 686 (D.C. Cir. 2000). Specifically, the
NOx state budgets represent the EPA’s projection for NOx
emissions in 2007 for each state if highly cost-effective con-
trols were implemented. ‘‘Highly cost-effective’’ is defined as
those controls capable of removing NOx at a cost of $2,000 or
less per ton. See Appalachian Power Co. v. EPA, 251 F.3d
1026, 1030 (D.C. Cir. 2001).
The EPA adopted the second rule in response to petitions
from eight states requesting a finding, pursuant to CAA
section 126(b), 42 U.S.C. § 7426(b), that stationary sources in
upwind states were contributing to ozone non-attainment in
the petitioning states in violation of the CAA. 42 U.S.C.
§ 7410(a)(2)(D). Each petitioning state further sought direct
federal regulation of stationary sources in upwind states.
Because the Section 126 petitions raised many of the same
issues as the NOx SIP Call, the EPA coordinated its response
to the section 126 petitions with the NOx SIP Call rulemak-
ing. Based on the analysis underlying the NOx SIP Call, the
EPA determined that sources in all or parts of 12 states
contributed to non-attainment in the petitioning states;
therefore, the Agency established emission limits for major
NOx sources in those states. 65 Fed. Reg. 2674 (Jan. 18,
2000) (‘‘Section 126 Rule’’). As with the NOx SIP call, the
EPA considered both NOx emissions and the cost of control-
ling them in determining which sources contributed signifi-
cantly to downwind ozone non-attainment. The EPA also
established a ‘‘cap and trade’’ program for the Section 126
Rule, which allows sources with emissions that exceed their
budget to purchase allowances from other facilities.
NOx emissions budgets for both the Section 126 Rule and
the NOx SIP Call are calculated for the year 2007, although
states and EGUs must begin meeting their budgets on May
31, 2004. See 67 Fed. Reg. 21,522–21,525 (April 30, 2002).
Additionally, both rules rely on the same underlying determi-
nations. In setting the NOx budgets, the EPA divided each
6
state’s NOx emissions according to five source types or
‘‘sectors’’: EGUs, non-EGU stationary sources (such as in-
dustrial boilers), area sources (smaller stationary sources),
highway mobile sources, and nonroad mobile sources. The
EPA calculated budget allocations for each sector. See Appa-
lachian II, 251 F.3d at 1030. At issue in this petition is the
EPA’s method for determining the EGU budgets.
To calculate the EGU budgets, the EPA started with a
baseline utilization measured as heat input, in million British
thermal units (‘‘mmBtu’’), from fossil fuels for each EGU’s
actual heat input from 1995 or 1996, whichever was higher.
To that baseline, the EPA added a heat input growth factor.
To determine the growth factor, the EPA used the Integrated
Planning Model (‘‘IPM’’). Several assumptions went into the
IPM, one of the most critical of which was projected electrici-
ty demand for the states. The EPA utilized inputs derived
from the model for 2001–2010. The EPA then applied the
projected heat input growth for the 2001–2010 period to the
1995 or 1996 baseline to determine projected heat inputs for
the year 2007. Under the NOx SIP Call, each state can
allocate its NOx allowances to individual sources as it deems
appropriate. Under the Section 126 Rule, EPA distributed
the allowances to specific EGUs based on historical heat input
levels.
B. This Court’s Remands
We have previously considered petitions for review of both
the NOx SIP Call and the Section 126 Rule. In both cases
we remanded the rules and instructed the EPA to ‘‘fulfill its
obligation to engage in reasoned decisionmaking on how to
set EGU growth factors and explain why results that appear
arbitrary on their face are, in fact, reasonable determina-
tions.’’ Appalachian I, 249 F.3d at 1055; Appalachian II,
251 F.3d at 1035. This decision was based, at least in part,
on the fact that in two states ‘‘actual utilization in 1998
already exceeded the EPA’s projected level for 2007.’’ Appa-
lachian I, 249 F.3d at 1053. Additionally, the EPA’s implied
prediction of ‘‘negative growth in electricity generation over
7
the course of a decade appear[ed] arbitrary,’’ as it was left
completely unexplained. Id. ‘‘While courts routinely defer
to agency modeling of complex phenomena, model assump-
tions must have a ‘rational relationship’ to the real world.’’
Id. (citing Chemical Mfrs. Ass’n v. EPA, 28 F.3d 1259, 1265
(D.C. Cir. 1994)). In sum, although we noted that EPA’s
choice may have been reasonable, its failure to explain why it
made that choice was error, particularly in the face of con-
trary real-world data.
C. EPA’s Response on Remand
EPA published its response to this Court’s remands in the
Federal Register on May 1, 2002. 67 Fed. Reg. 21,868
(‘‘Remand Response’’). There, the EPA explained that it
decided to retain the previously determined growth rates and
provide a fuller explanation. The EPA first pointed out that
the 2001–2010 modeled period utilized a consistent set of
assumptions. While many commenters suggested using pre-
dicted annual growth rates in energy demand from 1995 or
1996 to 2007, the agency was ‘‘not aware of any projected
heat input growth rates for that period for each State TTT
that were developed using a consistent set of assumptions.’’
Id. at 21,875. According to the EPA, this Court had already
held that the EPA’s decision to rely upon the IPM instead of
inconsistent projections offered by individual states was not
arbitrary and capricious. Appalachian I, 249 F.3d at 1052–
53. The EPA also noted that the two time periods at issue
overlap substantially and run a similar length of time. 67
Fed. Reg. 21,875. Furthermore, the EPA explained that the
increased costs in man-hours and dollars associated with
adding extra years to the model would require ‘‘simplifying
other assumptions within the model,’’ thus decreasing its
accuracy. Id. at 21,876. In addition, by utilizing the years
2001–2010, the IPM results could be used in a variety of EPA
programs, including implementation of the recently revised
NAAQS for ozone. Id. at 21,875.
The EPA also addressed this Court’s concerns regarding
the difference between EPA’s predictions and actual heat
8
input levels at the time of the earlier Appalachian cases.
Using data for the two years following those decisions, the
EPA points out that heat input in the two states cited as
inconsistent with EPA’s predictions—Michigan and West Vir-
ginia—had significantly dropped. Id. at 21,882–90. The
Remand Response explained that most of the regulated
states’ actual heat input values are now consistent with EPA’s
predictions, and none are so far above EPA’s predictions as to
indicate that its assumptions are incorrect. The Agency also
conducted a historical analysis of heat input, which showed
that it is quite variable and subject to both up and down
swings. Thus, heat input can decline over multi-year periods.
Id. at 21,884–85.
Following EPA’s publication of its Remand Response, two
states and several business entities petitioned this Court for
review. They claim, inter alia, that the EPA’s projections
remain arbitrary, that EPA’s use of the 2001–2010 modeling
years is unsupportable, and that EPA’s predictions regarding
future electricity demand were unreasonable.
II. Analysis
This Court sets aside EPA final action under the CAA if
that action is arbitrary, capricious, an abuse of discretion, or
otherwise not in accordance with law. 42 U.S.C. § 7607(d)(9).
The standard of review is the same for the NOx SIP Call,
which is not subject to § 7607(d)(9), but is subject to the
Administrative Procedure Act. 5 U.S.C. § 706(2)(A). Under
this familiar standard, ‘‘[a]gency determinations based upon
highly complex and technical matters are ‘entitled to great
deference.’ ’’ Appalachian I, 249 F.3d at 1051–52 (quoting
Public Citizen Health Research Group v. Brock, 823 F.2d
626, 628 (D.C. Cir. 1987)). See also Huls Am., Inc. v.
Browner, 83 F.3d 445, 452 (D.C. Cir. 1996) (‘‘[W]e will give an
extreme degree of deference to the agency when it ‘is evaluat-
ing scientific data within its technical expertise.’ ’’) (citation
omitted). This is particularly true when we review the use of
computer models because ‘‘their scientific nature does not
easily lend itself to judicial review.’’ Appalachian Power Co.
9
v. EPA, 135 F.3d 791, 802 (D.C. Cir. 1998). The EPA has
‘‘undoubted power to use predictive models’’ as long as it
‘‘explain[s] the assumptions and methodology used.’’ Small
Refiner Lead Phase–Down Task Force v. EPA, 705 F.2d 506,
535 (D.C. Cir. 1983). We will ‘‘defer to the agency’s decision
on how to balance the cost and complexity of a more elabo-
rate model against the oversimplification of a simpler model.’’
Id. We will vacate if the agency’s conclusions drawn from
this model are unreasonable.
A. Standing
We first address the standing of petitioner States. The
EPA contends that West Virginia and Illinois do not have
standing to challenge the Agency’s action, arguing that these
States are suing as parens patriae on behalf of electric
generators inside their respective borders. While it is true
that ‘‘[a] State does not have standing as parens patriae to
bring an action against the Federal Government,’’ that is not
the case before us. Maryland People’s Counsel v. FERC,
760 F.2d 318, 320 (D.C. Cir. 1985) (internal citations omitted).
Here, the states are suing as states.
The NOx SIP Call directs each state to revise its SIP in
accordance with EPA’s NOx emissions budget for the state.
The lower the emissions budget, the more difficult and oner-
ous is the states’ task of devising an adequate SIP. Thus,
lower growth factors leading to lower emissions budgets
causes injury to the states as states. EPA’s own brief belies
its argument, as it states that ‘‘[u]nder the NOx SIP Call,
states have the option of participating in [a] cap and trade
program or obtaining the reductions through other mecha-
nisms.’’ This injury is sufficient to confer standing. Cf. City
of Olmstead Falls v. FAA, 292 F.3d 261, 268 (D.C. Cir. 2002)
(declining to decide whether a city may sue as parens patriae
because injury to the city itself suffices for standing).
B. EPA’s Failure to Provide an Opportunity for Comment
Petitioner States challenge EPA’s failure to provide formal
notice-and-comment after adding data to the docket on re-
10
mand. According to petitioner States, the CAA requires
EPA to engage in formal notice-and-comment procedures
when promulgating or revising a SIP (under 42 U.S.C.
§ 7410(c)) or taking action under Section 126. 42 U.S.C.
§ 7607(d)(1)(B), (N). During the remand proceedings, the
EPA published a Notice of Data Availability (‘‘NODA’’) that
stated that the growth rates could ‘‘be supported with a more
robust explanation, based on the existing record.’’ 66 Fed.
Reg. 40,609 (Aug. 3, 2001). In addition, the EPA stated it
was ‘‘considering new data’’ that ‘‘appear[ed] to confirm the
reasonableness of the growth calculations.’’ Id. EPA invited
comment and gave thirty days to respond.
On March 11, 2002, EPA released its second NODA
(‘‘NODA II’’). 67 Fed. Reg. 10,844. After listing 15 docu-
ments, the EPA offered no invitation to comment. Id. De-
spite the lack of an invitation, Illinois responded and asked
for clarification of what had been added to the record and also
requested the opportunity to have ‘‘meaningful review and
comment.’’ Illinois also reasserted the concerns it had raised
in the first NODA and reattached them for EPA’s consider-
ation. Id.
The EPA contends that no notice-and-comment was re-
quired, because our earlier Appalachian I & II cases merely
remanded for a fuller explanation. As such, on remand no
notice-and-comment was required because EPA was only
providing a better explanation, not engaging in rulemaking.
The EPA also claims that even if notice-and-comment were
required it complied because, although it did not expressly
request comment in NODA II, it did receive comments.
Petitioner States have the better argument. The EPA
erred in not providing an opportunity to comment when it
added new material to the record subsequent to its publica-
tion of the first NODA. The CAA specifically requires that
EPA shall specify a comment period for any ‘‘action of the
Administrator under [Section 126].’’ 42 U.S.C.
§ 7607(d)(1)(N), (d)(3).
This Court, however, will invalidate agency action because
of procedural error only if the error is ‘‘so serious and related
11
to matters of such central relevance to the rule that there is a
substantial likelihood that the rule would have been signifi-
cantly changed if such error[ ] had not been made.’’ Nation-
al Petrochemicals & Refiners Ass’n v. EPA, 287 F.3d 1130,
1148 (D.C. Cir. 2002) (quoting CAA § 307(d)(8), 42 U.S.C.
§ 7607(d)(8)). Petitioner States argue that EPA’s refusal to
conduct full notice-and-comment rulemaking fails under this
standard. The only support petitioner States offer for this
proposition, however, is their contention that had the states
been given meaningful opportunity for comment, Illinois
would have been able to offer evidence about its nuclear
power and electricity generation capacity that would have
countered EPA’s assumptions. This example is not convinc-
ing.
In its response to NODA II, Illinois stated that it had
already ‘‘provided detailed support for [Illinois’ position that
EPA’s projected electrical generation was too low] to EPA
and we have explained our analyses and supporting facts in
detail.’’ Illinois pointed out that during the NODA I com-
ment period, it had commented on the ‘‘data and on the
broader underlying growth factor issues which Illinois has
repeatedly raised to EPA.’’ In Illinois’ response to NODA I,
it specifically provided its opinion regarding its nuclear power
generation and capacity. In sum, the only evidence petition-
ing States offer to show that the absence of formal proce-
dures following NODA II caused EPA to decide differently
was, in fact, before the EPA in responses to NODA I. This is
not sufficient under the applicable standard of review. While
EPA erred in failing to provide comment following NODA II,
petitioners have offered no evidence that there is a ‘‘substan-
tial likelihood’’ that the rule would have been ‘‘significantly
changed’’ in the absence of the procedural error.
C. EPA’s Growth Factor Methodology
This Court previously found that the EPA failed to explain
its method for projecting EGU growth rates. In Appala-
chian I and Appalachian II, we remanded the rules at issue
and instructed the EPA to ‘‘fulfill its obligation to engage in
12
reasoned decisionmaking on how to set EGU growth factors
and explain why results that appear arbitrary on their face
are, in fact, reasonable determinations.’’ Appalachian I, 249
F.3d at 1055; Appalachian II, 251 F.3d at 1035. In particu-
lar, we were concerned about EPA’s decision to apply project-
ed heat input growth rates from 2001–2010 to the 1996–2007
period. Appalachian I, 249 F.3d at 1053–54. Fueling those
concerns was our observation that real-world growth rates
were not in line with EPA’s projections. Id. Petitioners
contend that on remand the agency has failed to satisfy its
obligation to resolve these concerns.
According to petitioners, the overlapping quality of the
time periods is irrelevant, because 2001–2010 is not represen-
tative of 1996–2007. In particular, petitioners argue that
there is an absence of evidence regarding heat-input growth
for the 1996–2000 period. If growth rates during that time
period were different, it would set all of the EPA’s predic-
tions askew, because the IPM uses the difference between
two modeled years to determine the growth rate. In other
words, according to petitioners, the starting point matters
greatly in determining the end result, as the years build on
one another. Furthermore, petitioners do not accept the
agency’s explanation that the high costs in conducting extra
IPM runs militate against adding runs for the additional
years 1996–2001, and they question the EPA’s explanation
that by running the IPM for 2001–2010, the EPA will be able
to utilize the information for several other programs. In
sum, petitioners argue that EPA cannot rely on generalized
cost savings as an excuse for limiting the quality of its work.
We think EPA has reasonably explained why it chose to
rely on the IPM projections for years 2001–2010 in determin-
ing the projected growth rate for 1996–2007. We pause to
note that actual heat inputs have changed since our prior
decisions. The discrepancies we observed between the actual
heat input values and the projections for various states during
the original Appalachian cases – which discrepancies made
EPA’s modeled growth rates appear arbitrary – are no longer
so severe. Both West Virginia and Michigan, which were
cited in our earlier opinions as having actual heat input in
13
1998 already exceeding the EPA’s 2007 projections, have both
experienced declining heat input from 1998 to 2001. Appala-
chian I, 249 F.3d at 1053. By 2001, the last year for which
data was available for EPA’s Remand Response, Michigan’s
heat input levels had dropped significantly and were in line
with EPA’s 2001 projections and 8.7% below 2007 projections.
67 Fed. Reg. 21,895. Furthermore, actual heat-input values
have decreased in several of the regulated states from 1998 to
2001. 67 Fed. Reg. 21,883. Finally, EPA points out that the
NOx SIP Call covers 23 jurisdictions, and the existence of
some margin of error with respect to some of the predictions
is not indicative of an unreasonable approach.
In response to our concern that ‘‘[f]uture growth projec-
tions that implicitly assume a baseline of negative growth in
electricity generation over the course of a decade appear
arbitrary, and the EPA can point to nothing in the record to
dispel this appearance,’’ Appalachian I, 249 F.3d at 1053, the
EPA has published historical data that shows there have been
historical periods of multi-year heat-input decline. 67 Fed.
Reg. 21,884–21,885.
The EPA also points out the significant overlap between
the modeled time period and the regulated time period.
Again, the IPM was run for the years 2001–2010, and then
applied to the 1995 or 1996 to 2007 time frame. Therefore,
for the 2001–2007 period, all of the underlying inputs would
be the same as if the model had been conducted on the 1995
or 1996 to 2007 time period. The resulting projected demand
for those years would also be the same. Because the growth
factor is derived from the difference in heat input growth
between modeled years, for this entire period the growth rate
is directly correlated.
Finally, the EPA describes its effort to ‘‘balance the cost
and complexity of a more elaborate model against the over-
simplification of a simpler model.’’ Id. at 21,876 (quoting
Small Refiner Lead Phase–Down Task Force v. EPA, 705
F.2d 506, 535 (D.C. Cir. 1983)). As the EPA explains, ‘‘[t]he
complexity of the model – its simulations, inputs, and varia-
bles – means that each additional run year adds many more
14
calculations to the model, a task that requires time and
resources.’’ Id. Because of the increased cost, ‘‘other ways
would have had to be [sic] found to reduce the number of
equations,’’ including reduction of variables or constraints
which would have decreased the accuracy of the model. Id.
In addition, by starting the IPM in 2001, ‘‘the model ade-
quately served the needs of several programs.’’ Id. In sum,
EPA asserts that any further refinement in the heat input
growth rate that may have resulted from adding additional
years would not have been worth the increased cost.
In the Appalachian cases we were faced with a situation in
which ‘‘even in the face of evidence suggesting the EPA’s
projections were erroneous, the EPA never explained why it
adopted this particular methodology.’’ Appalachian I, 249
F.3d at 1053. On remand, EPA adequately explained why it
chose to apply IPM results from 2001–2010 to determine 2007
heat input requirements, and the evidence suggesting the
projections were erroneous has greatly diminished. As we
stated in the earlier cases, we will ‘‘give an extreme degree of
deference to the agency when it is evaluating scientific data
within its technical expertise.’’ Id. at 1052 (quoting Huls
Am., Inc. v. Browner, 83 F.3d 445, 452 (D.C. Cir. 1996)).
Furthermore, ‘‘we must defer to the agency’s decision on how
to balance the cost and complexity of a more elaborate model
against the oversimplification of a simpler model.’’ Small
Refiner Lead Phase–Down Task Force v. EPA, 705 F.2d at
535. We will ‘‘reverse only if the model is so oversimplified
that the agency’s conclusions from it are unreasonable.’’ Id.
This great degree of deference, coupled with EPA’s explana-
tion and the evidence added to the record on remand, re-
quires that the petitions be denied.
D. EPA’s Electrical Demand Projections
and Disaggregation
Petitioners raise two other distinct challenges. First, they
claim that the EPA erred in projecting electricity demand
growth. More specifically, petitioners contend that EPA
erred in discounting electricity demand projections made by
15
the North American Electric Reliability Council (‘‘NERC’’), a
not-for-profit corporation made up of electric utility genera-
tors, sellers, and users. Petitioners also challenge EPA’s
reduction of projections made by the Energy Information
Administration (‘‘EIA’’), a department within the United
States Department of Energy. The EPA made these reduc-
tions because it thought the forecasts did not take into
account future reductions in electricity demand caused by
energy conservation programs. Petitioners challenge both
the amount of the reduction EPA applied, and the premise
that these energy conservation programs were not already
accounted for in the projections.
Second, they challenge EPA’s method of disaggregating
regional data. Because the IPM ‘‘necessarily models electric-
ity generation and sales on a regional basis in order to reflect
the regional nature of the electricity sector,’’ EPA is required
to take regional results and turn them into state-specific
budgets. 67 Fed. Reg. 21,888. Petitioners contend that EPA
failed to adequately explain its disaggregation methodology,
and that failure to do so on remand was arbitrary.
Both petitioners’ disaggregation and electricity demand
reduction claims are forfeit. The EPA correctly points out
that petitioners never raised these claims to the agency in the
administrative proceedings when the modeling period was
adopted, or in the earlier challenges in this Court. To the
extent that petitioners challenged the validity of EPA’s use of
the IPM, this Court has already rejected that challenge.
Appalachian I, 249 F.3d at 1052–53. Petitioners, having
forgone the ability to attack these aspects of the model while
the rule was being promulgated and initially challenged in
court, cannot now do so. Appalachian II, 251 F.3d at 1036
(‘‘It is black-letter administrative law that ‘absent special
circumstances, a party must initially present its comment to
the agency during the rulemaking in order for the court to
consider the issue’ ’’) (quoting Tex Tin Corp. v. EPA, 935
F.2d 1321, 1323 (D.C. Cir. 1991)). Because neither of these
claims were raised in the initial litigation or the original
rulemaking, they cannot be raised now.
16
Additionally, EPA did not reopen these issues in the re-
mand proceedings. Petitioners argue vehemently that EPA
did so because it ‘‘respond[ed] on the merits’’ to virtually all
comments. 67 Fed. Reg. 21,901. That statement in the
Federal Register, however, was made in response to commen-
ters’ request that EPA treat any comments it believed out-
side the scope of the remand as a petition to reconsider. Id.
As we have previously held, ‘‘the reopening rule of Ohio v.
EPA is not a license for bootstrap procedures by which
petitioners can comment on matters other than those actually
at issue, goad an agency into a reply, and then sue on the
grounds that the agency had re-opened [sic] the issue.’’
American Iron & Steel Inst. v. EPA, 886 F.2d 390, 398 (D.C.
Cir. 1989) (internal citations omitted). Petitioners are correct
that ‘‘[w]hether an agency has in fact reopened an issue,
explicitly or implicitly,’’ depends on ‘‘the entire context of the
rulemaking including all relevant proposals and reactions of
the agency.’’ Public Citizens v. NRC, 901 F.2d 147, 150 (D.C.
Cir. 1990). However, petitioners have not shown that the
EPA either explicitly or implicitly reconsidered these issues
on remand.
As a threshold matter, EPA expressly stated on remand
that it ‘‘is not soliciting comment on IPM itself or on state-
specific approaches for determining 2007 heat input levels.’’
66 Fed. Reg. 40,616 (August 3, 2001). Looking for implicit
reconsideration of these claims, we find none. A reading of
EPA’s explanation of its reduction of EIA and NERC fore-
casts, contained in its Remand Response, shows that it did
not reconsider that aspect of the rule; rather, it responded to
commenters’ concerns by further explaining its reasoning.
See Fed. Reg. 21,867–21,881. This is also true of its di-
saggregation methodology. The EPA’s disaggregation meth-
odology was made public on August 24, 1998. 63 Fed. Reg.
45,032–45,033. Petitioners, however, did not raise any claims
about EPA’s disaggregation methodology in the previous
litigation. Again, a reading of the EPA’s Remand Response
shows that there was no implicit reconsideration of its
disaggregation methodology; instead, it simply reiterated the
17
reasoning it had used from the beginning. 67 Fed. Reg.
21,881.
In sum, these claims fall squarely within the ambit of
American Iron & Steel Institute. Here, petitioners submit-
ted comments, ‘‘goad[ed] [EPA] into a reply, and [now] sue on
the grounds that the agency ha[s] re-opened [sic] the issue.’’
American Iron & Steel Inst. 886 F.2d at 398. This, we cannot
allow. The record does not reflect that EPA explicitly or
implicitly reopened the issue. See Public Citizens v. NRC,
901 F.2d at 150.
III. Conclusion
The EPA erred in not providing an opportunity to comment
when it added new material to the docket subsequent to its
initial NODA, but because the petitioners have not shown a
substantial likelihood that the rule would have been signifi-
cantly changed in the absence of that procedural error, it will
not serve as the basis for invalidating the agency’s action.
Because EPA has now explained its choice of methodology for
projecting EGU growth factors, and because petitioners’
claims regarding: (1) EPA’s reduction of NERC and EIA
forecasts, and (2) EPA’s disaggregation methodology have
been waived, we deny the petitions for review.