                     FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

EL COMITÉ PARA EL BIENESTAR DE              
EARLIMART, an unincorporated
association; COMMUNITY &
CHILDREN’S ADVOCATES AGAINST
PESTICIDE POISONING, a California
non-profit corporation WISHTOYO
FOUNDATION, a California non-
profit corporation VENTURA
COASTKEEPER, a California non-
profit corporation ASSOCIATION OF
IRRITATED RESIDENTS, an                           No. 06-16000
unincorporated association,
                 Plaintiffs-Appellees,
                                                   D.C. No.
                                                CV-04-00882-LKK
                 and
AIR COALITION TEAM,
                           Intervenor,
                  v.
MARY-ANN WARMERDAM,* in her
official capacity as Director
Department of Pesticide
Regulation; LINDA ADAMS, in her
official capacity as Secretary, CA
                                            
   *Mary-Ann Warmerdam is substituted for Paul Heliker, her predecessor
as Director of the CA Department of Pesticide Regulation; Linda Adams
is substituted for Terry Tamminen, her predecessor as Secretary, CA Envi-
ronmental Protection Agency; James Goldstene is substituted for Cather-
ine Witherspoon, his predecessor as Executive Officer, CA Air Resources
Board; Mary Nichols is substituted for Alan Lloyd, her predecessor as
Chair, CA Air Resources Board. See Fed. R. App. P. 43(c)(2). The follow-
ing new members of the California Air Resources Board are substituted
for the previous members: Daniel Sperling, Jerry Hill, Doreen D’Adamo,
Barbara Riordan, John R. Balmes, Lydia Kennard, Sandra Berg, Ron Rob-
erts, John G. Telles and Ronald O. Loveridge.

                                 11179
11180             EL COMITÉ v. WARMERDAM


Environmental Protection Agency;       
JAMES GOLDSTENE, in his official
capacity as Executive Officer, CA
Air Resources Board; MARY
NICHOLS, in her official capacity as
Chair, CA Air Resources Board;
WILLIAM BURKE, in his official
capacity as Member, CA Air
Resources Board; CA JOSEPH
CALHOUN, in his official capacity
as Member, CA Air Resources
Board; DORENE D’ADAMO, in her
official capacity as Member, CA
Air Resources Board; MARK
DESAULNIER, in his official capacity
as Member, CA Air Resources
Board; C. HUGH FRIEDMAN, in his
official capacity as Member, CA        
Air Resources Board; MATTHEW
MCKINNON, in his official capacity
as Member, CA Air Resources
Board; BARBARA PATRICK, in her
official capacity as Member, CA
Air Resources Board; BARBARA
RIORDAN, in her official capacity
as Member, CA Air Resources
Board; RON ROBERTS, in his
official capacity as Member, CA
Air Resources Board; ROBERT F.
SAWYER, Chair, CA Air Resources
Board; WILLIAM F. FRIEDMAN, in
his official capacity as Member,
CA Air Resources Board,
              Defendants-Appellants.
                                       
                   EL COMITÉ v. WARMERDAM              11181



EL COMITÉ PARA EL BIENESTAR DE          
EARLIMART, an unincorporated
association; COMMUNITY &
CHILDREN’S ADVOCATES AGAINST
PESTICIDE POISONING, a California
non-profit corporation WISHTOYO
FOUNDATION, a California non-
profit corporation VENTURA
COASTKEEPER, a California non-
profit corporation ASSOCIATION OF
IRRITATED RESIDENTS, an
unincorporated association,
                Plaintiffs-Appellees,
AIR COALITION TEAM,                           No. 06-16131

                                        
               Intervenor-Appellant,            D.C. No.
                 v.                         CV-04-00882-LKK
MARY-ANN WARMERDAM, in her                     OPINION
official capacity as Director
Department of Pesticide
Regulation; LINDA ADAMS, in her
official capacity as Secretary, CA
Environmental Protection Agency;
JAMES GOLDSTENE, in his official
capacity as Executive Officer, Air
Resources Board; MARY NICHOLS,
in her official capacity as Chair,
CA Air Resources Board; WILLIAM
BURKE, in his official capacity as
Member, CA Air Resources
Board; JOSEPH CALHOUN, in his
                                        
11182              EL COMITÉ v. WARMERDAM


official capacity as Member, CA        
Air Resources Board; DORENE
D’ADAMO, in her official capacity
as Member, CA Air Resources
Board; MARK DESAULNIER, in his
official capacity as Member, CA
Air Resources Board; C. HUGH
FRIEDMAN, in his official capacity
as Member, CA Air Resources
Board; MATTHEW MCKINNON, in
his official capacity as Member,
CA Air Resources Board;
BARBARA PATRICK, in her official
capacity as Member, CA Air
Resources Board; BARBARA
RIORDAN, in her official capacity      
as Member, CA Air Resources
Board; RON ROBERTS, in his
official capacity as Member, CA
Air Resources Board,
                         Defendants,
WILLIAM F. FRIEDMAN, in his
official capacity as Member, Air
Resources Board,
                          Defendant,
                 and
ROBERT F. SAWYER, Chair, CA Air
Resources Board,
               Defendant-Appellant.
                                       
         Appeal from the United States District Court
            for the Eastern District of California
        Lawrence K. Karlton, District Judge, Presiding
               EL COMITÉ v. WARMERDAM             11183
               Argued and Submitted
       May 12, 2008—San Francisco, California

                Filed August 20, 2008

Before: Diarmuid F. O’Scannlain, Michael Daly Hawkins,
      and M. Margaret McKeown, Circuit Judges.

             Opinion by Judge McKeown
                  EL COMITÉ v. WARMERDAM                 11185


                         COUNSEL

Edmund G. Brown, Jr., Attorney General of the State of Cali-
fornia, James Humes, Chief Deputy Attorney General, Tom
Greene, Chief Assistant Attorney General, Mary E. Hacken-
bracht, Senior Assistant Attorney General, John Davidson,
Supervising Deputy Attorney General, Michael W. Neville,
Deputy Attorney General of California, San Francisco, Cali-
fornia, for the defendants-appellants.

Jan L. Kahn and Rissa A. Stuart, Hanford, California, for
appellant-intervenors.

Brent Newell and Luke W. Cole, Center for Race, Poverty &
the Environment, San Francisco, California, for the plaintiffs-
appellees.


                         OPINION

McKEOWN, Circuit Judge:

  This case involves a challenge under § 304 of the Clean Air
Act (“CAA”), see 42 U.S.C. § 7604(a), known as the citizen
suit provision. A coalition of community organizations (“El
Comité”) brought suit against California state officials
11186              EL COMITÉ v. WARMERDAM
(“California”) responsible for designing and implementing a
state air quality plan. The complicated approval process for
the State Implementation Plan (“SIP”) required much back-
and-forth between California and the Environmental Protec-
tion Agency (“EPA”). El Comité takes issue with both the
process by which California obtained EPA approval of the
SIP and the final outcome of that approval process. In particu-
lar, El Comité argues that California violated federal law by
failing to adhere to the SIP approved by the EPA, which it
argues required California to implement additional regulations
in five areas where air quality standards for reducing harmful
emissions have not been met. California went astray, accord-
ing to El Comité, by using the wrong data to calculate the
baseline for its emission standards and by ignoring deadlines
that were intended to be incorporated into EPA’s final
approval of the SIP. El Comité’s claim turns on determination
of what documents were incorporated into the final SIP and
the EPA rule, and interpretation of what the SIP, and hence
federal law, requires of California.

   The district court concluded that it did not have jurisdiction
to review El Comité’s claim regarding the data and methodol-
ogy used by California to calculate the baseline for emissions
standards. The court agreed, however, with El Comité’s
expansive interpretation of the SIP, and ordered relief based
on that interpretation. That relief was also built on the meth-
odology El Comité advocated for use in calculating the base-
line — the same methodology the district court had held it
was without jurisdiction to review. As it carefully worked
through the parties’ labyrinthine administrative law argu-
ments, the court acknowledged that its rulings were poten-
tially incongruous. We agree. In our view, the district court
ultimately exceeded its jurisdiction. Because § 304 of the
CAA provides jurisdiction only to enforce an “emission stan-
dard or limitation,” and because the challenged conduct did
not implicate such a standard or limitation, the court was
without jurisdiction to order a remedy.
                   EL COMITÉ v. WARMERDAM               11187
I.    FACTUAL AND PROCEDURAL BACKGROUND

     A.   THE SIP PROCESS UNDER THE CLEAN AIR ACT

   To protect public health and welfare, the CAA requires the
EPA to establish National Ambient Air Quality Standards
(“NAAQS”) for certain air pollutants. 42 U.S.C. § 7409. The
Act places much of its enforcement burden on the states,
which are required to submit SIPs that show how states will
attain the standards for major air pollutants. Id. § 7410.
Before a SIP becomes effective, the EPA must determine that
it meets the CAA’s requirements. Id. § 7410(k)(3). Once the
EPA approves a SIP, it becomes federal law. Safe Air for
Everyone v. EPA, 488 F.3d 1088, 1091 (9th Cir. 2007); Bay-
view Hunters Point Cmty. Advocates v. Metro. Transp.
Comm’n, 366 F.3d 692, 695 (9th Cir. 2004);

   Each state is required to designate the areas within its
boundaries where the air quality meets the NAAQS
(“attainment areas”), and those where the air quality fails to
meet the NAAQS (“nonattainment areas”) for each pollutant
targeted for emissions reductions. 42 U.S.C. § 7407(d)(1)(A).
SIPs must include an attainment demonstration, a technical
analysis that through air quality modeling demonstrates that
the “control measures” proposed by the SIP will ensure that
these nonattainment areas attain the NAAQS by the applica-
ble deadline. Id. § 7502(c)(1). Plan provisions for nonattain-
ment areas must contain “enforceable emission limitations,
and such other control measures, means or techniques (includ-
ing economic incentives such as fees, marketable permits, and
auctions of emission rights), as well as schedules and timeta-
bles for compliance, as may be necessary or appropriate to
provide for attainment” by the deadline. Id. § 7502(c)(6); see
also Sierra Club v. EPA, 356 F.3d 296, 299 (D.C. Cir. 2004).
11188                EL COMITÉ v. WARMERDAM
  B.    CALIFORNIA’S 1994 SIP PROCESS AND EPA REVIEW
        AND APPROVAL

   Under threat of an EPA takeover of the state’s air quality
planning, the California Air Resources Board (“CARB”), the
state agency responsible for preparing and submitting a SIP
for EPA approval, submitted the 1994 SIP. See Cal. Health &
Safety Code § 39602. The SIP includes a subsection (known
as “the Pesticide Element”) prepared by the California
Department of Pesticide Regulation (“DPR”) that proposes
strategies for reducing volatile organic compound (“VOC”)1
emissions from agricultural and commercial structural pesti-
cides.

   The Pesticide Element set a “goal” of reducing, by 2005,
pesticide-related emissions from the 1990 baseline by a “max-
imum of 20 percent,” and provided that “a decision whether
additional regulatory measures to ensure that reductions in
pesticidal VOC emissions are achieved will be made by
1997” (emphasis added). A timeline at the end of the Pesti-
cide Element states that the decision on regulations will be
made by November 1997, with the implementation of the plan
to occur by December 1998. The plan’s summary also states
that by December 1998, “[i]mplementation of additional regu-
latory measures, if necessary, will take place to ensure that
targeted pesticidal VOC reductions occur” (emphasis added).

   After California submitted the Pesticide Element, consider-
able discussion took place through correspondence between
David Howekamp, Director of EPA Region IX Air Division,
and DPR Director James Wells. Howekamp expressed con-
cern that the proposed SIP was not complete enough for EPA
review. Specifically, EPA was concerned that the SIP lacked
specific emission reduction goals specified by date and nonat-
tainment area, and that the SIP did not propose a firm dead-
  1
   VOCs mix with oxides of nitrogen (NOx) in heat and sunlight to form
ground-level ozone, i.e., smog.
                   EL COMITÉ v. WARMERDAM                 11189
line by which California committed to deciding whether to
adopt new emissions regulations for several nonattainment
areas. To fill these gaps, Howekamp proposed that California
“explicitly” commit to a decision deadline of June 15, 1997,
and suggested emission reduction goals by nonattainment
area.

   California capitulated to EPA’s requests in a May 11, 1995,
letter from James Boyd, then executive officer for CARB, to
the EPA, stating that he was “transmit[ting] a clarification” of
the Pesticide Element of the 1994 SIP, and noting that the
“enclosed letter from DPR clarifies that in the SIP, California
has committed to adopt and submit to U.S. EPA by June 15,
1997, any regulations necessary to achieve the emission
reductions from pesticides specified in the letter.” Letter from
Boyd to EPA, May 11, 1995 (emphasis added). The enclosed
“letter” was a May 9, 1995, memorandum from Wells to
Boyd (“the Wells Memorandum”). The Wells Memorandum
stated the same commitment referenced in Boyd’s cover letter
and included a table outlining interim reduction goals for each
nonattainment area.

   When the EPA issued its Notice of Proposed Rulemaking,
the summary of the Proposed Rules identified the Wells
Memorandum as a “clarification” of the “technical details of
the pesticide commitment” and stated that the “clarification is
considered part of California’s SIP.” Approval and Promulga-
tion of Implementation Plans; California—Ozone, 61 Fed.
Reg. 10920, 10935 (March 18, 1996) (to be codified at 40
C.F.R. pt. 52) (“Proposed Rules”). Following the close of the
public comment period, but before the Final Rule issued,
CARB sent a letter dated June 13, 1996 to Howekamp
(“Howekamp letter”) seeking to clarify and correct various
aspects of the SIP, in particular, to delete the table from the
Wells letter labeled “Reductions from 1990 Pesticide Emis-
sions Baselines.” This deletion effectively erased any record
indicating the interim target reductions for the nonattainment
areas. Following this modification, the EPA approved the
11190             EL COMITÉ v. WARMERDAM
1994 SIP on January 8, 1997. See Approval and Promulgation
of Implementation Plans; California—Ozone,62 Fed. Reg.
1150, 1186-87; 40 C.F.R. § 52.220(c)(204)(i)(A)(6) (1997).

   In February, four months before the June 15, 1997, dead-
line for deciding whether to adopt regulations, a DPR scientist
called into question CARB’s methodology— “back-casting,”
or extrapolating backwards from 1991 data— for calculating
the 1990 baseline inventory. Back-casting is the methodology
stated in the Pesticide Element. The scientist proposed instead
calculating the 1990 baseline with 1990 data from the Pesti-
cide Use Report (“PUR”). Although there is no contempora-
neous evidence of the decision to switch methodologies, a
public workshop package released by DPR in February 1998
confirms that the department adopted the scientist’s approach
of using the 1990 PUR data.

   By the time the June 15 deadline arrived, California had
decided it was unnecessary to adopt additional regulations.
This decision is documented in a February 1998 letter from
Wells in response to a Notice of Intent to Sue under the Clean
Air Act sent by the Environmental Defense Center. Wells’s
letter states that

    [o]ur April 1997 analysis of data through 1995
    showed that all nonattainment areas (NAAs) were
    meeting annual interim goals, and that four out of
    five were already meeting the final 2005 year goals
    . . . . Therefore, we determined in April 1997 that no
    regulations were necessary to reduce VOC emissions
    by specific percentages. Consequently, no regula-
    tions were adopted and submitted to U.S. EPA in
    June 1997.

  C.    THE CITIZEN SUIT AND DISTRICT COURT ORDERS

  El Comité filed a citizen suit under § 304 of the Clean Air
Act, 42 U.S.C. § 7604(a), to enforce the 1994 SIP. El Com-
                   EL COMITÉ v. WARMERDAM                 11191
ité’s amended complaint includes two claims. The first count
alleges that various California agencies “violated an emission
standard or limitation by failing to adopt regulations to reduce
pesticide-related VOC emissions by June 15, 1997,” as
required by the Wells Memorandum’s clarification of the
1994 SIP. The second count alleges that, in using the 1990
PUR data rather than the 1991 back-cast data, the state vio-
lated an emission standard or limitation because it manipu-
lated the 1990 baseline to avoid the obligation to adopt new
regulations by June 15, 1997.

   The district court issued an order granting El Comité’s
summary judgment motion on the first count (holding that
California failed to adopt regulations in 1997), and granting
California’s motion on the second count (holding that the
court did not have jurisdiction over the claim that California
violated the SIP by use of the wrong methodology to calculate
the baseline data), and denying the parties’ motions in all
other respects. El Comité Para el Bienestar de Earlimart v.
Helliker, 416 F. Supp. 2d 912, 934 (E.D. Cal. 2006). The dis-
trict court judge, somewhat prescient about the issues before
us on appeal, found himself “bemused by the result,” but
nonetheless stated, “the result, while ironic, is not inconsis-
tent.” Id. at 916 n.5.

   The court issued a second order on remedies (“Remedies
Order”) providing injunctive and declaratory relief to El
Comité. The Remedies Order requires California to “propose,
adopt, and submit to EPA for approval and implement regula-
tions no later than January 1, 2008, to achieve the emission
reduction goals as set forth in the May 9, 1995, memorandum
from James Wells to James Boyd,” and to file a status report
as to its progress.

   The Remedies Order also declared that the defendants “are
in violation” of the CAA and the 1994 SIP by “failing to uti-
lize the 1990 PUR data as set forth in the 1994 SIP and by
failing to adopt ‘enforceable control measures’ ” as required
11192                  EL COMITÉ v. WARMERDAM
by the CAA. In reaching this conclusion, the district court
reiterated its earlier conclusion that a SIP must have enforce-
able standards to be valid, and while the court had not explic-
itly held that California failed to comply with the SIP by
virtue of the failure to adopt and implement regulations, the
“record undoubtedly reflects that [California] failed to meet
the promises it made in the SIP, including failing to use the
correct PUR data.” The court reasoned, “[b]y virtue of [the]
failure to use the correct PUR data, the [California] defen-
dants consequently were unable to adopt proper ‘enforceable
control measures,’ as they must, under the Clean Air Act.”
California appealed the summary judgment in favor of El
Comité on the first claim and the Remedies Order.

II.   ANALYSIS

   Despite a complicated factual background, the dispute here
is not factual, but rather, is a matter of regulatory interpreta-
tion and administrative law principles. Our review is de novo.
See Arakaki v. Haw., 314 F.3d 1091, 1094 (9th Cir. 2002). To
determine whether California violated the SIP, and whether
the remedies imposed by the district court are appropriate, we
first address the scope of the Final SIP. On this issue, the par-
ties hotly contest the significance of the Wells Memorandum,
the Howekamp letter, and a declaration by Howekamp pre-
pared for this litigation.2

   El Comité argues that we cannot consider the revisions to
the SIP contained in the Howekamp letter because they were
submitted by California to the EPA after the public comment
period had closed, and since no other revision rescinded the
Wells Memorandum, that memorandum and the Howekamp
  2
   The two references to Howekamp documents are easily confused. The
so-called letter to Howekamp was actually authored by CARB on June 13,
1996, but addressed to Howekamp. This document is referred to as “the
Howekamp letter.” Howekamp also authored the Howekamp declaration
as part of this litigation, well after leaving his position at EPA Region IX.
                   EL COMITÉ v. WARMERDAM                  11193
declaration reflect EPA’s understanding of California’s com-
mitments under the SIP, i.e., its administrative intent in
approving the SIP. California argues that the Final SIP
excludes the Wells Memorandum, and under principles of
administrative law, we are precluded from considering admin-
istrative intent because the regulation is unambiguous. Cali-
fornia also questions the validity of Howekamp’s declaration,
which it describes as an “ex post facto declaration” by a “pri-
vate citizen.”

   Because we conclude that the schedule and interim stan-
dards of the Wells Memorandum are not part of the SIP, Cali-
fornia would not have been in violation of the SIP even if it
had made no decision about the need for further regulations.
And significantly, any such decision would have been discre-
tionary by the language of the SIP (“a decision whether addi-
tional regulatory measures to ensure that reductions in
pesticidal VOC emissions are achieved will be made by
1997” (emphasis added)). Nonetheless, El Comité argues that
by using the 1990 data rather than the 1991 back-cast data,
California violated the SIP by failing to adopt “enforceable
control measures.” The district court held—and we agree—
that the baseline methodology is not “an emission standard or
limitation” that falls within the district court’s jurisdiction
under § 304 of the CAA, 42 U.S.C. § 7604(a). It necessarily
follows that the district court also lacked jurisdiction to
impose remedies based on the alleged deficiency in the base-
line methodology.

  A.   THE SCOPE OF THE SIP

   The parties frame the key issue as a debate over whether
the Wells Memorandum is included in the Final SIP. The
heart of El Comité’s case is cut out if the memorandum is not
part of the Final SIP. On the other hand, if the memorandum,
with its detailed interim requirements and fixed date of June
15, 1997, is part of an enforceable SIP, then the case is cast
in a very different light. The district court stated that “neither
11194                 EL COMITÉ v. WARMERDAM
the statute, the regulatory process, nor the record provide a
clear resolution to the problem.” We think the issue is not as
open-ended as the district court portrays it because the lan-
guage of the final rule is not ambiguous.

   California’s arguments on this point are persuasive. It
argues that the district court erred in its analysis by ignoring
40 C.F.R. § 52.220, which catalogs revisions to the California
SIP but which contains no reference to the Wells Memoran-
dum. See 40 C.F.R. § 52.02(f) (“Revisions to applicable plans
will be included in this part when approved or promulgated by
the Administrator.”).3 In general, “[t]he promulgated provi-
sions, together with any portions of a State plan approved by
the Administrator, constitute the applicable plan for purposes
of the Act.” 40 C.F.R. 52.02(b). Instead, the court relied on
two other sources that have little legal traction: (1) certain lan-
guage in the preamble published in the Notices of Proposed
and Final Rulemaking in the Federal Register (“Proposed
Rule” and “Final Rule,” respectively);4 and (2) Howekamp’s
declaration.
  3
     All documents that EPA incorporates into the SIP under § 52.220 must
be filed with the Office of the Federal Register and approved for incorpo-
ration by reference by the Director of the Federal Register. See 40 C.F.R.
§ 52.02(d). Such documents must be available at three separate locations:
the National Archives and Records Administration; EPA’s Office of Air
and Radiation Docket Information Center in Washington, D.C.; and the
appropriate EPA regional office. Although not definitive, it bears noting
that California filed a Freedom of Information Act request for the EPA to
produce all documents that “create, clarify, revise or amend” the DPR’s
obligations under the SIP that were held at any of these locations. EPA’s
response produced the 1994 Pesticide Element and the 1996 Howekamp
letter, but not the Wells Memorandum.
   4
     California points out that the operative language in the Federal Regis-
ter, whereby the EPA exercises its delegated legislative rulemaking
authority, is the language that amends the Code of Federal Regulations
(“Part 52, chapter I, title 40 of the Code of Federal Regulations is
amended as follows”), and that all text prior to this reference is preamble.
See 62 Fed. Reg. at 1186.
                    EL COMITÉ v. WARMERDAM                    11195
     1.   The Preamble

   [1] Regarding the first source, the preamble language
should not be considered unless the regulation itself is ambig-
uous. See Wards Cove Packing Corp. v. Nat’l Marine Fish-
eries Serv., 307 F.3d 1214, 1219 (9th Cir. 2002) (“[T]he plain
meaning of a regulation governs and deference to an agency’s
interpretation of its regulation is warranted only when the reg-
ulation’s language is ambiguous.” (citing Christensen v. Har-
ris County, 529 U.S. 576, 588 (2000)). The D.C. Circuit took
a similar approach in Wyoming Outdoor Council v. United
States Forest Service, 165 F.3d 43, 53 (D.C. Cir. 1999),
explaining that “in the analogous context of statutory con-
struction . . . the language in the preamble of a statute is ‘not
an operative part of the statute . . . .’ ” That is, unlike the stat-
ute’s operative part, the preamble does not “prescribe rights
and duties and otherwise declare the legislative will,” nor
does it “enlarge or confer powers on administrative agencies
or officers,” but it nevertheless “may aid in achieving a gen-
eral understanding of the statute.” Id. (internal quotation
marks omitted). By analogy, the “principles governing inter-
pretation of the preamble of a regulation are no different” than
those governing statutory interpretation, and thus, “[w]here
the enacting or operative parts of a statute are unambiguous,
the meaning of the statute cannot be controlled by the lan-
guage in the preamble.” Id.

   [2] El Comité assumes the regulatory language is ambigu-
ous because of the controversy over the Wells Memorandum
—that the Proposed Rules referenced the document as a revi-
sion, but the Final Rule excluded it among the official revi-
sions approved by EPA. In doing so, El Comité offers a
circular argument and glosses over the framework for regula-
tory interpretation, emphasizing the language of the preamble
above all else. And even if the regulations were ambiguous
and the preamble properly considered as evidence of context
or intent, the preamble to the Final Rule contains a summary
11196                   EL COMITÉ v. WARMERDAM
of California’s submissions by date of submission that clearly
does not include the Wells Memorandum.5

   El Comité also misapplies the proposition in Safe Air that
a court interprets a SIP based on its “plain meaning when
such a meaning is apparent, not absurd, and not contradicted
by the manifest intent of EPA, as expressed in the promulgat-
ing documents available to the public.” 475 F.3d at 1108
(emphasis added). Invoking Safe Air, El Comité looks past the
plain meaning of the Final Rule, which excludes the Wells
Memorandum and any reference to it, and focuses instead on
the proposed rule’s incorporation of the Wells Memorandum
as proof of EPA’s administrative intent.

   [3] El Comité’s reliance on the non-final rule ignores the
bedrock principle that we look to the plain meaning of the
final rule as promulgated. See Bayview, 366 F.3d at 698 (“A
regulation should be construed to give effect to the natural
and plain meaning of its words”) (citation omitted).). As part
of the rule making process, on June 13, 1996, California
wrote to Howekamp at EPA, providing information and cor-
  5
    The introduction to the summary of the preamble of the Final Rule
states:
      EPA is approving revisions to the California State Implementa-
      tion Plan (SIP) for ozone for 6 nonattainment areas . . . . In addi-
      tion, EPA is approving specific local and statewide air pollution
      control measures . . . . The California Air Resources Board
      (CARB) submitted these SIP revisions to EPA on November 14,
      1994, November 15, 1994, December 28, 1994, December 29,
      1994, February 7, 1995, March 30, 1995, January 22, 1996, April
      4, 1996, May 17, 1996, June 13, 1996 (Howekamp Letter), July
      10, 1996, and July 12, 1996.
        EPA is approving these revisions to the California SIP under
      provisions of the Clean Air Act (CAA) regarding EPA action on
      SIP submittals for nonattainment areas.
62 Fed. Reg. at 1150. Notably absent from this list of approved SIP revi-
sions is CARB’s transmission of the Wells Memorandum on May 11,
1995.
                  EL COMITÉ v. WARMERDAM                 11197
rections to the SIP. The letter requested that EPA excise the
interim goals table in the Wells Memorandum. The Final SIP
lists the June 1996 letter but does not reference the Wells
Memorandum other than in the preamble’s summary, and
there the table is excised according to the instructions in the
Howekamp letter. Thus the Howekamp letter became the final
word in the saga of the SIP.

   The difficulty with the Howekamp letter, El Comité sug-
gests, is that it was submitted over a month after the public
comment period had closed and thus cannot be part of the SIP
because EPA’s administrative intent to modify the 1994 SIP
was not made available for public consideration and com-
ment. See Safe Air, 475 F.3d at 1105-06 (“[T]he notice
requirements of the APA, [require] that some indication of the
regulatory intent that overcomes plain language must be refer-
enced in the published notices that accompanied the rulemak-
ing process. Otherwise, interested parties would not have the
meaningful opportunity to comment on proposed regulations
that the APA contemplates, because they would have had no
way of knowing what was actually proposed” (citations omit-
ted).).

   El Comité’s focus on administrative intent puts the cart
before the horse. We are justified in considering administra-
tive intent only if the regulation is ambiguous, as was argu-
ably the case in Safe Air. The difficulty with relying on Safe
Air in this case is that in Safe Air we did not address which
documents were and were not part of the SIP—the central
issue that concerns us here. Rather, Safe Air involved inter-
pretation of a SIP whose contents were already established. It
is also significant that Safe Air involved a challenge under
§ 307(b)(1) to the propriety of a rulemaking proceeding, not
a challenge to an emission standard under § 304.

   [4] El Comité’s argument takes us in a direction we cannot
follow because it implicates a question over which we lack
jurisdiction: whether, in revising the SIP along the lines
11198              EL COMITÉ v. WARMERDAM
requested by California and allowing a modification of the
SIP after the close of the public comment period, the EPA
violated the Administrative Procedure Act. See generally
Ober v. EPA, 84 F.3d 304, 313 (9th Cir. 1996) (“An agency
may use supplementary data, unavailable during the notice
and comment period, that expands on and confirms informa-
tion contained in the proposed rulemaking and addresses
alleged deficiencies in the pre-existing data, so long as no
prejudice is shown” (quoting Idaho Farm Bureau Fed’n v.
Babbitt, 58 F.3d 1392, 1402 (9th Cir. 1995)) (emphasis
added).). That question is the quintessential administrative
challenge under a petition to review a final decision of the
EPA (see 42 U.S.C. § 7607(b)(1)), such as was at issue in
Safe Air, 475 F.3d at 1103. It is one we do not have jurisdic-
tion to decide in this appeal, however, because this case was
filed under § 304, 42 U.S.C. § 7604(a).

    2.    The Howekamp Declaration

  As part of its analysis of intent and whether the Wells
Memorandum was incorporated into the final SIP, the district
court looked to Howekamp’s Declaration. Significantly, this
declaration was offered not by an EPA representative but by
a former employee some years after the fact. We need not
consider the exact scope and admissibility of such intent evi-
dence because, in any event, it cannot override the plain lan-
guage of the regulation or EPA’s contemporaneous statements
published in the Federal Register.

  [5] In sum, we conclude that the district court erred in hold-
ing that the Wells Memorandum was incorporated into the
SIP.

  B.     THE BACK-CAST METHODOLOGY ESTABLISHING THE
         BASELINE INVENTORY IS NOT AN EMISSION STANDARD
         OR LIMITATION


  In the district court, El Comité challenged California’s use
of the 1990 data instead of the 1991 back-cast data. Califor-
                   EL COMITÉ v. WARMERDAM                 11199
nia’s use of the improper methodology, El Comité argued,
made it impossible for the state to assess whether new regula-
tions were needed, thereby rendering unenforceable the com-
mitment to adopt regulations, if necessary, by June 15, 1997,
and making the entire SIP invalid under the CAA. After ana-
lyzing the nature of the baseline inventory, the district court
granted summary judgment in favor of California: “[El Com-
ité’s] second claim fails because a ‘baseline inventory’ is not
an ‘emission standard or limitation’ subject to challenge under
the Clean Air Act.” El Comité, 416 F. Supp. 2d at 927. The
district court found that the baseline inventory is not an emis-
sion standard or limitation under the statute because it does
not “limit[ ] the quantity, rate, or concentration of emissions
of air pollutants on a continuous basis,” and does not “relat[e]
to the operation or maintenance of a source to assure continu-
ous emission reduction.”

   Although El Comité did not appeal this issue, its arguments
nonetheless implicitly quarrel with this finding. Citing Bay-
view, El Comité attempts to skirt the gap in our jurisdiction
by shifting its argument on appeal, claiming that if the SIP is
understood to impose an obligation to reduce emissions in
nonattainment areas, then the baseline inventory (and by
extension, the way it is calculated) are necessary elements of
this enforceable commitment. This argument attempts to
transform the baseline inventory into an enforceable emission
standard or limitation by bootstrapping it to the commitment
to decide to adopt regulations, if necessary. While we
acknowledge that the baseline is a critical foundation, this
does not change our view that neither the baseline nor the
methodology qualify as independently enforceable aspects of
the SIP. Bayview is not to the contrary. See Bayview, 366 F.3d
at 703 (holding that “Bayview’s citizen suit represents an
inappropriate attempt to alter [the] explicit provisions” of a
SIP). We emphasize this point because it bears on the issue
of remedies.
11200             EL COMITÉ v. WARMERDAM
  C.    THE DISTRICT COURT LACKED JURISDICTION TO ISSUE A
        REMEDIES ORDER

   [6] The district court declared that California violated the
CAA and the California SIP by “failing to adopt ‘enforceable
control measures’ as required by the [CAA].” Remedies
Order at 2; see also Remedies Order at 3 n.2 (“[B]y virtue of
their failure to use the correct PUR data, defendants conse-
quently were unable to adopt proper ‘enforceable control
measures,’ as they must, under the Clean Air Act.”). Because
neither the Wells Memorandum nor the baseline data provide
an enforceable emission standard or limitation, no relief is
available to El Comité under § 304 of the CAA, 42 U.S.C.
§ 7604(a). Nor would the district court have jurisdiction to
hold, in effect, that the EPA improperly approved an invalid
SIP because it lacked enforceable emission standards. That
challenge, and any related relief, falls outside the purview of
the district court and would have to be brought as a petition
to review the EPA’s rulemaking process. See 42 U.S.C.
§ 7607(b)(1).

   [7] We reverse the summary judgment in favor of El
Comité, vacate the Remedies Order, and remand with orders
to dismiss the case for lack of jurisdiction.

  REVERSED AND REMANDED.
