                  FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

OUR CHILDREN’S EARTH                   
FOUNDATION, and ECOLOGICAL
RIGHTS FOUNDATION; ECOLOGICAL
RIGHTS FOUNDATION,
              Plaintiffs-Appellants,
                v.
UNITED STATES ENVIRONMENTAL
PROTECTION AGENCY; MICHAEL O.               No. 05-16214
LEAVITT, Administrator of EPA;                D.C. No.
STEVEN L. JOHNSON,
             Defendants-Appellees,
                                          CV-04-02132-PJH
                                            ORDER AND
ASSOCIATION OF METROPOLITAN                   OPINION
SEWERAGE AGENCIES; EFFLUENT
GUIDELINES INDUSTRY COALITION;
THE UTILITY WATER ACT GROUP
(UWAG); NATIONAL
ASSOCIATION OF CLEAN WATER
AGENCIES (NACWA),
            Defendant-Intervenors-
                          Appellees.
                                       
       Appeal from the United States District Court
          for the Northern District of California
       Phyllis J. Hamilton, District Judge, Presiding

                  Argued and Submitted
       February 13, 2007—San Francisco, California

                    Filed May 23, 2008

    Before: J. Clifford Wallace, Dorothy W. Nelson, and
          M. Margaret McKeown, Circuit Judges.

                            5983
5984   OUR CHILDREN’S EARTH v. EPA
       Opinion by Judge McKeown
5986            OUR CHILDREN’S EARTH v. EPA


                         COUNSEL

Christopher Sproul, Environmental Advocates, San Francisco,
California, for the appellant.

Sue Ellen Wooldridge, Assistant Attorney General, Washing-
ton, DC, for the appellees.

Fredric P. Andes, Carolyn S. Hesse, and David T. Ballard,
Barnes & Thornburg, L.L.P., Chicago, Illinois, for intervenor-
appellee Effluent Guidelines Industry Coalition.

David W. Burchmore and Jill A. Grinham, Squire, Sanders,
& Dempsey L.L.P., Cleveland, Ohio, for intervenors-
appellees Association of Metropolitan Sewerage Agencies,
now known as National Association of Clean Water Agen-
cies.

Melanie Shepherdson, National Resources Defense Counsel,
Washington, DC, amicus in support of the appellants.

Jeffrey Odefey, Waterkeeper Alliance, Tarrytown, New York,
amicus in support of the appellants.


                          ORDER

  The petition for panel rehearing is granted. The petition for
rehearing en banc is denied as moot.
                    OUR CHILDREN’S EARTH v. EPA                         5987
  The opinion filed October 29, 2007, slip op. 14215, and
appearing at 506 F.3d 781, is withdrawn. It may not be cited
as precedent by or to this court or any district court of the
Ninth Circuit. It is replaced by the concurrently filed opinion.


                                OPINION

McKEOWN, Circuit Judge:

   In 1972 Congress passed the Clean Water Act (“CWA” or
“the Act”) “to restore and maintain the chemical, physical,
and biological integrity of the Nation’s waters.” See Federal
Water Pollution Control Act Amendments of 1972 (Clean
Water Act of 1972), Pub. L. No. 92-500, 86 Stat. 816 (1972)
(codified at 33 U.S.C. § 1251(a)). Central to that legislation
and later amendments is the notion that pollution discharges
would be controlled through technology-based effluent limita-
tions.

   Environmental advocates, Our Children’s Earth Foundation
and Ecological Rights Foundation (collectively “OCE”), filed
this citizen suit under the Clean Water Act, 33 U.S.C. § 1251
et seq., alleging that the Environmental Protection Agency
(“EPA” or “the Agency”) has failed to fulfill its mandate to
review effluent guidelines and limitations in a timely manner
and in accord with technology-based standards. Specifically,
OCE claims that EPA violated its statutorily-mandated duties
by abandoning technology-based review in favor of hazard-
based review; neglecting to identify new polluting sources;
and failing to publish timely plans for future reviews. See
CWA § 301(b), 33 U.S.C. § 1311(b); CWA § 301(d), 33
U.S.C. § 1311(d); CWA § 304(b), 33 U.S.C. § 1314(b); CWA
§ 304(m), 33 U.S.C. § 1314(m).1
   1
     Sections of the Clean Water Act, 33 U.S.C. § 1251 et seq., are conven-
tionally cited using the sections of the original Act, rather than the section
numbers assigned after codification in the U.S. Code. We follow that con-
vention here. The first time we cite to a provision of the Act, we include
a preliminary parallel citation to the U.S. Code. All citations are to the
CWA unless indicated otherwise.
5988              OUR CHILDREN’S EARTH v. EPA
   A technology-based approach to water quality focuses on
the achievable level of pollutant reduction given current tech-
nology, whereas a hazard-based2 approach seeks to identify
known hazards or contaminants in the water and to reduce the
prevalence of those hazards. See, e.g., S. Rep. No. 92-414, at
8 (1971), 1972 U.S.C.C.A.N. 3668, 3674-78. Although these
approaches are not mutually exclusive, OCE claims that EPA
jettisoned a technology-based approach altogether, thus abdi-
cating its statutory duties.

   The district court granted judgment in favor of EPA, hold-
ing that the challenged acts or omissions were discretionary.
We agree that the decisions whether to revise the effluent
guidelines and whether to incorporate technology-based
criteria in its periodic review of the guidelines fall within
EPA’s discretion. Consequently, we affirm.

                           BACKGROUND

  OCE’s amended complaint contains four claims alleging
non-compliance with what OCE characterizes as EPA’s man-
datory duties under the Act:

  (1) EPA failed to review effluent guidelines based on the
“best conventional pollutant technology” (“BCT”) and “best
available technology” (“BAT”), as mandated by §§ 304(b),
(m);

  (2) EPA failed to review existing effluent limitations as
required by §§ 301(b), (d);

   (3) EPA failed to issue timely final effluent guidelines
plans as required by § 304(m)(1); and
  2
   Hazard-based regulation is also referred to in the record as water-
quality-based and harm-based regulation.
                   OUR CHILDREN’S EARTH v. EPA                       5989
  (4) EPA failed to identify new polluting sources as
required by § 304(m)(1)(B).

   In sum, OCE argues that the CWA requires, as a non-
discretionary matter, that the Agency take a particular
approach to water safety regulation: technology-based review,
published in a sufficiently timely fashion to afford a meaning-
ful opportunity for notice and comment. EPA and Intervenors
Effluent Guidelines Industry Coalition and Association of
Metropolitan Sewerage Agencies (now known as the National
Association of Clean Water Agencies) (together, “Interve-
nors”) counter that EPA’s non-discretionary duties do not
extend to a particular manner of performing reviews and revi-
sions.

   We first address the argument by EPA and the Intervenors
that this suit was not properly brought under the citizen suit
provision of the Act, § 505(a), 33 U.S.C. § 1365(a)(2), but
rather should have been brought under § 509(b)(1), 33 U.S.C.
§ 1369(b)(1). Then, we consider whether the district court has
jurisdiction over each of OCE’s four claims under
§ 505(a)(2). Because § 505(a)(2) jurisdiction is predicated on
citizen enforcement of a non-discretionary duty, our analysis
focuses on whether the claims relate to discretionary or non-
discretionary duties under the Act.

                               ANALYSIS

        I.   JURISDICTION TO REVIEW AGENCY ACTION3
  3
   The Agency’s position on jurisdiction is not entitled to deference under
Chevron U.S.A., Inc. v. Natural Res. Def. Council, Inc., 467 U.S. 837
(1984). See, e.g., Fox Television Stations, Inc. v. FCC, 280 F.3d 1027,
1038-39 (D.C. Cir. 2002) (“Nor is an agency’s interpretation of a statutory
provision defining the jurisdiction of the court entitled to our deference
under Chevron.”) (citing Adams Fruit Co. v. Barrett, 494 U.S. 638, 650
(1990)).
5990                OUR CHILDREN’S EARTH v. EPA
   [1] The CWA contains two separate jurisdictional sections:
§ 505(a), known as the citizen suit provision, and § 509(b)(1),
which relates primarily to challenges to promulgation of cer-
tain standards and determinations. OCE brought suit under
§ 505(a)(2), which permits “any citizen [to] commence a civil
action on his own behalf . . . against the Administrator where
there is alleged a failure of the Administrator to perform any
act or duty under this chapter which is not discretionary with
the Administrator.”4 CWA § 505(a)(2).

  [2] Alternatively, § 509(b)(1) permits suits against the EPA
Administrator for review of action

      (A) in promulgating any standard of performance
      under section 1316 of this title, (B) in making any
      determination pursuant to section 1316(b)(1)(C) of
      this title, (C) in promulgating any effluent standard,
      prohibition, or pretreatment standard under section
      1317 of this title, (D) in making any determination
      as to a State permit program submitted under section
      1342(b) of this title, (E) in approving or promulgat-
      ing any effluent limitation or other limitation under
      section 1311, 1312, 1316, or 1345 of this title, (F) in
      issuing or denying any permit under section 1342 of
      this title, and (G) in promulgating any individual
      control strategy under section 1314(l). . . .

Suits brought pursuant to § 509(b)(1) must be filed directly

      in the Circuit Court of Appeals of the United States
      for the Federal judicial district in which [petitioner]
      resides or transacts business. . . . Any such applica-
      tion shall be made within 120 days from the date of
      such determination, approval, promulgation, issu-
  4
   OCE’s amended complaint also cites the Administrative Procedure Act
(“APA”), 5 U.S.C. §§ 702, 706, as an alternative basis for jurisdiction, but
does not allege any claims under the APA.
                OUR CHILDREN’S EARTH v. EPA                  5991
    ance or denial, or after such date only if such appli-
    cation is based solely on grounds which arose after
    such 120th day.

CWA § 509(b)(1). Section 509(b)(1) actions, as opposed to
suits brought under § 505(a)(2), challenge the exercise of the
Administrator’s discretion in promulgating standards and
issuing determinations.

   [3] So long as EPA’s challenged acts and omissions relate
to non-discretionary duties under the Act, OCE’s action was
properly brought in the district court under § 505(a)(2). To the
extent OCE challenges actions within the discretion of the
Administrator, the district court properly refused to exercise
jurisdiction under § 505(a)(2). Nonetheless, a jurisdictional
defect under § 505(a)(2) does not mean that jurisdiction is
proper under § 509(b)(1).

   “[T]his Court has counseled against expansive application
of section [509(b)].” League of Wilderness Defenders v. Fors-
gren, 309 F.3d 1181, 1190 n.8 (9th Cir. 2002). Section
509(b)(1) covers only challenges to “promulgation” or “ap-
proval” or “determinations” on permits, not failure to comply
with allegedly mandated procedures, which is the thrust of
OCE’s suit.

   Additionally, § 509(b)(1) lists a number of sections for
which review obtains in the court of appeals: §§ 301, 1312,
304(l), 1316, 1317, 1342, and 1345. Neither §§ 304(b) or
304(m) is referenced in § 509(b)(1). Because the challenge
here does not stem from the promulgation or approval of an
effluent limitation or permit, we need not decide whether
§ 509(b) encompasses a challenge under § 304. Compare E.I.
du Pont de Nemours & Co. v. Train, 430 U.S. 112, 136-37
(1977) (suggesting that the EPA could collapse the limitations
to be promulgated under §§ 301 and 304 into a single review),
with Longview Fibre Co. v. Rasmussen, 980 F.2d 1307, 1310
(9th Cir. 1992) (holding that the sections listed in § 509 are
5992             OUR CHILDREN’S EARTH v. EPA
sufficiently specific that unlisted sections should not be inter-
preted to be covered by § 509).

   [4] We thus agree with the district court that the circuit
court’s exclusive jurisdiction “extends only to a substantive
review of the appropriateness of the guidelines actually pro-
mulgated, and not to the threshold question of whether the
statutory requirements of the CWA have been met.” No such
promulgated guidelines or limitations are at issue here. The
district court had jurisdiction under § 505(a)(2) to determine
whether EPA discharged its non-discretionary duties under
the CWA.

       II.   TECHNOLOGY-BASED REVIEW AND REVISION

   In determining whether OCE’s four claims challenge non-
discretionary obligations under the Act, our point of reference
is the statute itself. Although the line between a congressional
mandate and an area of agency discretion is not difficult to
state, ascertaining that line is not always as easy. When Con-
gress specifies an obligation and uses the word “shall,” this
denomination usually connotes a mandatory command. See
Alabama v. Bozeman, 533 U.S. 146, 153 (2001). On the other
hand, “[a]bsent some provision requiring EPA to adopt one
course of action over the other, we can only conclude that
EPA’s choice represented an exercise of discretion.” Farmers
Union Cent. Exch. v. Thomas, 881 F.2d 757, 761 (9th Cir.
1989).

   However, not every decision is so easily categorized. As
the Supreme Court teaches, the decision-making process does
not necessarily collapse into a single final decision. “It is rudi-
mentary administrative law that discretion as to the substance
of the ultimate decision does not confer discretion to ignore
the required procedures of decisionmaking.” Bennett v. Spear,
520 U.S. 154, 172 (1997). In Bennett, considering a citizen
suit provision parallel to that in the CWA, the Supreme Court
held, “[s]ince it is the omission of these required procedures
                 OUR CHILDREN’S EARTH v. EPA                  5993
that petitioners complain of, their . . . claim is reviewable.” Id.
at 172 (emphasis added).

  With these general principles in mind, we consider the
CWA provisions relevant to each of OCE’s claims to deter-
mine whether the particular claim relates to a mandatory obli-
gation or discretionary agency function under the Act.

        A.   HISTORY OF THE CWA        AND   TECHNOLOGY

   By way of brief overview, when the CWA was enacted in
1972, its stated goal was the elimination of all discharges of
pollutants into the nation’s waters by 1985. See CWA
§ 101(a)(1); 33 U.S.C. § 1251(a)(1). This goal was to be
accomplished through ambitious technological improvements,
because the previous water-quality based approach to pollu-
tant control had been “limited in its success.” S. Rep. No. 92-
414, at 8 (1971), 1972 U.S.C.C.A.N. at 3675. In the CWA’s
Declaration of Goals and Policy, Congress wrote, “it is the
national policy that a major research and demonstration effort
be made to develop technology necessary to eliminate the dis-
charge of pollutants into the navigable waters, waters of the
contiguous zone, and the oceans.” CWA § 101(a)(6).

    The CWA formally prohibits the “discharge of any pollu-
tant” from any source into navigable waters except when
authorized by a permit issued under the National Pollutant
Discharge Elimination System (“NPDES”). See CWA
§ 301(a). NPDES permits, issued either by the EPA, or by the
states in a federally-approved permitting system, are statu-
torily required to set forth, at the very least, “effluent
limitations”—that is, certain “restriction[s] . . . on [the] quan-
tities, rates, and concentrations of chemical, physical, biologi-
cal, and other constituents which are discharged . . . into
navigable waters.” Waterkeeper Alliance, Inc. v. EPA, 399
F.3d 486, 491 (2d Cir. 2005) (citing S. Fla. Water Mgmt. Dist.
v. Miccosukee Tribe of Indians, 541 U.S. 95 (2004)).
5994            OUR CHILDREN’S EARTH v. EPA
   The specific effluent limitations contained in each NPDES
permit are determined by the terms of more general “effluent
limitation guidelines,” which are separately promulgated by
the EPA. The effluent limitations and the guidelines have long
been understood to be determined according to the best avail-
able or practicable technology. See E.I. du Pont de Nemours
& Co., 430 U.S. at 121 (explaining the technology-based
character of effluent limitations and guidelines); see also
Waterkeeper Alliance, 399 F.3d at 491 (“[Effluent Limitation
Guidelines], and the effluent limitations established in accor-
dance with them, are technology-based restrictions on water
pollution. They are technology-based, because they are estab-
lished in accordance with various technological standards that
the Act statutorily provides . . . .”).

   Since 1972 Congress has amended the CWA on a number
of occasions. In the 1985 amendments, Congress reaffirmed
its commitment to a technology-based approach to water qual-
ity regulation:

    The technology-based approach to water pollution
    control was adopted in 1972 because of the historical
    ineffectiveness of the previous water-quality-based
    approach. This approach failed because of uncertain-
    ties about the relationship between pollutant loadings
    and water quality and the association between water
    quality and health and environmental effects. There
    are still significant gaps in knowledge of these rela-
    tionships. Consequently the reported bill reaffirms
    the technologically-based approach established in
    1972 as an immediate and effective method of
    achieving the goals of the Act.

S. Comm. on Env’t & Pub. Works, 99th Cong., Report to
Accompany S. 1128 (1985 Clean Water Act Amendments) 3-
4 (Comm. Print 1985).
                    OUR CHILDREN’S EARTH v. EPA           5995
               B.    THE STATUTORY FRAMEWORK

   [5] Three key statutory provisions of the CWA are at issue
here: §§ 301(d), 304(b) and 304(m). Section 301(d) requires
EPA to review, every five years, the effluent limitations
established under § 301(b)(2) and to revise such regulations
“if appropriate.” These processes are undergirded by a series
of mandated criteria stating what the regulations “shall” con-
tain. The mandated criteria include technology-based require-
ments. See CWA § 304. Sections 304(b) and (m) require an
annual review of “guidelines for effluent limitations” applica-
ble to direct dischargers and revision “if appropriate.” As in
§ 301, § 304(b) includes mandated criteria that reference
technology-based requirements, without differentiating
between application of these criteria to promulgation, review
or revision. Section 304(m) specifically provides for a sched-
ule for review of the guidelines in accordance with § 304(b).

   According to EPA, rather than conducting separate
reviews, it consolidates effluent limitations required under
§ 301(d) into effluent limitation guidelines under § 304(b). As
EPA puts it: “through its annual review of its consolidated
‘effluent limitation guidelines’ EPA also reviews the effluent
limitations they contain, thus meeting its review requirements
under § 301(d) and § 304(b) simultaneously.”

          C.    CRITERIA FOR REVIEW AND REVISION

   It is undisputed that EPA has an obligation to review efflu-
ent guidelines and limitations for possible revision, and that
such a review is mandatory. It is also undisputed that EPA’s
ultimate decision whether to revise the guidelines and limita-
tions is discretionary, as “appropriate.” And, it is undisputed
that any revision must be in accord with detailed statutory
criteria that incorporate variants of the best-technology stan-
dard. What remains in dispute is whether, as part of its man-
dated review process, EPA must consider the technology-
5996            OUR CHILDREN’S EARTH v. EPA
based criteria. To address this question, we consider the stat-
ute itself.

   [6] The Act imposes on EPA non-discretionary duties to
review its current effluent limitations guidelines regulating
the pollutants discharged into the nation’s waters, and, “where
appropriate,” to revise them, according to the criteria in the
statute. See CWA §§ 301(d); 304(b), (m). Under § 304(b),
“the Administrator shall, after consultation with appropriate
Federal and State agencies and other interested persons, pub-
lish within one year of October 18, 1972, regulations, provid-
ing guidelines for effluent limitations, and, at least annually
thereafter, revise, if appropriate, such regulations.” The stat-
ute goes on to provide that “[s]uch regulations shall” conform
to specific criteria. The requirement of a technology-based
approach to promulgation and revision of regulations runs
throughout the statutory text of § 304(b).

  Section 304(b)(1)(A) states:

    Such regulations shall—identify . . . the degree of
    effluent reduction attainable through the application
    of the best practicable control technology currently
    available for classes and categories of point sources
    ....

CWA § 304(b)(1)(A).

  Section 304(b)(1)(B) relates that the regulations “shall”:

    specify factors to be taken into account . . . relating
    to the assessment of best practicable control technol-
    ogy currently available . . . includ[ing] consideration
    of the total cost of application of technology in rela-
    tion to the effluent reduction benefits to be achieved
    from such application, and shall also take into
    account the age of equipment and facilities involved,
    the process employed, the engineering aspects of the
                   OUR CHILDREN’S EARTH v. EPA                       5997
      application of various types of control techniques
      . . . . and such other factors as the Administrator
      deems appropriate.5

CWA § 304(b)(1)(B).

  Section 304(b)(2)(A) continues to mandate a technology-
based approach, without differentiating between promulgation
and revision:

      regulations shall . . . identify, . . . the degree of efflu-
      ent reduction attainable through the application of
      the best control measures and practices achievable
      including treatment techniques, process and proce-
      dure innovations . . . .

CWA § 304(b)(1)(A).

   Section 304(b)(4)(A) yet again requires an analysis in terms
of “application of the best conventional pollutant control tech-
nology . . . .” Each of the subsections of § 304(b) includes a
mandatory requirement related to technology.

   [7] Under § 304(m), EPA also has an obligation to publish
a biennial plan announcing a schedule for performing the
annual review and for establishing rules regarding any exist-
ing effluent guideline selected for possible revision as a con-
sequence of the annual review. Section 304(m)(1) states in
full:

      (m)   Schedule for review of Guidelines
  5
   This last phrase, “and such other factors as the Administrator deems
appropriate,” indicates, as OCE acknowledges, that the EPA could adopt
additional factors for consideration, including harm or risk-based factors.
The discretion to consider additional factors does not, however, render the
mandatory factors optional.
5998            OUR CHILDREN’S EARTH v. EPA
       (1)   Publication

       Within 12 months after February 4, 1987, and
    biennially thereafter, the Administrator shall publish
    in the Federal Register a plan which shall—

         (A) establish a schedule for the annual review
    and revision of promulgated effluent guidelines, in
    accordance with subsection (b) of this section [speci-
    fying technology-based factors];

         (B) identify categories of sources discharging
    toxic or nonconventional pollutants for which guide-
    lines under subsection (b)(2) of this section and sec-
    tion 1316 of this title have not previously been
    published; and

         (C) establish a schedule for promulgation of
    effluent guidelines for categories identified in sub-
    paragraph (B), under which promulgation of such
    guidelines shall be no later than 4 years after Febru-
    ary 4, 1987, for categories identified in the first pub-
    lished plan or 3 years after the publication of the
    plan for categories identified in later published plans.

CWA § 304(m)(1).

   In § 301, which deals with the five year review and revision
of effluent limitations, Congress wrote: “Any effluent limita-
tion required by paragraph (2) of subsection (b) of this section
shall be reviewed at least every five years and, if appropriate,
revised pursuant to the procedure established under such para-
graph.” CWA § 301(d) (emphasis added). The cross-
referenced subsection (b)(2) mandates the application of
technology-based criteria in determining the applicable efflu-
ent limitations.

   For example, § 301(b)(2)(A) states that effluent limitations
for categories other than publicly-owned treatment works
                 OUR CHILDREN’S EARTH v. EPA                5999
“shall require application of the best available technology
economically achievable . . . .” The mandated technology-
based criteria run throughout the text of § 301(b). See, e.g.,
CWA § 301(b)(1)(A) (“[E]ffluent limitations . . . shall require
the application of the best practicable control technology cur-
rently available . . . .”); § 301(b)(2)(E) (“[P]ollutants identi-
fied . . . shall require application of the best conventional
pollutant control technology . . . .”).

   The plain language of these provisions reflects that the
CWA repeatedly mandates a technology-based approach as a
non-discretionary matter in the promulgation of the regula-
tions, at least as one methodology among others. Further, the
statute makes clear that the regulations must comport with
technological criteria that change over time. The statutory lan-
guage is unambiguous that revision decisions, although dis-
cretionary as indicated by the “if appropriate” language, are
constrained by the statute’s mandate as to what “such regula-
tions” “shall” accomplish. The statute states that the regula-
tions “shall” account for the technological factors without
distinguishing between promulgation and revision.

   [8] Nonetheless, while the overall structure of the Act
strongly suggests that any review to determine whether revi-
sion is appropriate should contemplate the mandatory
technology-based factors, the statute does not expressly and
unequivocally state as much. Nothing in the CWA specifi-
cally obligates the EPA to review the effluent guidelines and
limitations using a technology-based approach. At most, the
statutory provisions and legislative history are ambiguous.

  [9] To compel agency action under § 505(a)(2), a citizen
suit must point to a nondiscretionary duty that is “readily-
ascertainable” and not “only [ ] the product of a set of infer-
ences based on the overall statutory scheme.” Sierra Club v.
Thomas, 828 F.2d 783, 791 (D.C. Cir. 1987). The legislative
and regulatory maze presented here do not meet that standard.
Nor would it be appropriate for us to divine a “specific,
6000             OUR CHILDREN’S EARTH v. EPA
unequivocal command,” see Norton v. S. Utah Wilderness
Alliance, 542 U.S. 55, 63 (2004), from an amalgamation of
disputed statutory provisions and legislative history coupled
with the EPA’s own earlier interpretation. See Preliminary
Effluent Guidelines Plan for 2004-2005, 68 Fed. Reg. 250,
75515 (EPA Dec. 31, 2003). Finally, we do not invoke the
Chevron analysis here because we are not trying to determine
whether we should defer to the EPA’s interpretation of the
statute, but are trying to determine whether, objectively, the
statute creates a mandatory duty. In sum, the statute falls short
of imposing a mandatory duty and thus the review criteria are
not properly before the court under § 505(a)(2).

       III.   PUBLICATION SCHEDULE PROPOSED BY OCE

   [10] Section 304(m) requires biennial publication of a plan
for scheduling annual review and revision of the guidelines.
The plan must provide for public review and comment prior
to final publication. See CWA § 304(m)(2). OCE argues that
the plan should be synchronized with the annual review, but
as the district court correctly held, the Act does not require
this degree of harmonization.

   [11] The statute requires only that the EPA abide by the
time limitations requiring biennial publication. Nowhere does
the statute require that the EPA synchronize its publication
with the calendar year. OCE objects that use of the word
“plan” implies that it be published before the described events
take place. Although this argument has logical appeal, it is
insufficient to trump the text of the statute.

   [12] As long as the EPA meets the statutorily-prescribed
deadlines, and affords opportunity for notice and comment, it
has satisfied its mandatory duties under § 304(m). The publi-
cation schedule preferred by OCE is not mandated by the stat-
ute, and thus is not amenable to challenge under § 505(a)(2).
                 OUR CHILDREN’S EARTH v. EPA                 6001
     IV.   IDENTIFICATION OF NEW POLLUTING SOURCES

   OCE also argues that EPA has failed to identify new cate-
gories of industry discharging toxic and nonconventional pol-
lutants not covered by existing effluent guidelines. The
district court found that in 2005 EPA identified only two new
sources for which no guidelines then existed. According to
OCE, following EPA’s 2003 review, EPA proposed not to
schedule promulgation of any new effluent guidelines.

   [13] Under § 304(m)(1)(B), the Administrator “shall”
devise a plan which “shall—identify categories of sources dis-
charging toxic or nonconventional pollutants for which guide-
lines under subsection (b)(2) of this section and section 1316
of this title have not previously been published.” The Admin-
istrator is also required to schedule publication of effluent
guidelines for the categories identified under § 304 (m)(1)(B).
See CWA § 304(m)(1)(C).

   [14] The statute does not require that the Administrator
identify all or any existing categories of sources, only that the
Administrator identify currently unregulated categories. The
Senate Committee Report on the 1985 Amendments states:
“Guidelines are required for any category of sources discharg-
ing significant amounts of toxic pollutants. In this use, ‘signif-
icant amounts’ does not require the Administrator to make
any determination of environmental harm; any non-trivial dis-
charges from sources in a category must lead to effluent
guidelines.” S. Comm. on Env’t & Pub. Works, 99th Cong.,
Report to Accompany S. 1128 (1985 Clean Water Act
Amendments) 25 (Comm. Print 1985). The Senate Committee
Report suggests that it is at least within the discretion of the
Administrator to determine whether particular discharges are
non-trivial, and hence require new effluent guidelines.

   [15] While the identification of new categories is a non-
discretionary duty, the precise number and kind of such cate-
gories identified is discretionary with the Administrator. The
6002             OUR CHILDREN’S EARTH v. EPA
statutory language does not command otherwise. Since EPA
did identify two new categories of sources during the period
in question here, OCE’s challenge to the sufficiency of new
source identification is not properly brought under
§ 505(a)(2).

                  V.   MOTION TO TRANSFER

   After filing a notice of appeal to this court, OCE filed a
motion to transfer its claims to this court as if they were origi-
nally filed here under § 509(b)(1). The district court did not
abuse its discretion in refusing to transfer claims to this court
after the notice of appeal had been filed. See Griggs v. Provi-
dent Consumer Discount Co., 459 U.S. 56, 58 (1982) (per
curiam) (holding that once a notice of appeal is filed, the dis-
trict court is divested of jurisdiction over the matter being
appealed); see also Miller v. Hambrick, 905 F.2d 259, 262
(9th Cir. 1990) (a challenge to the district court’s refusal to
transfer claims under 28 U.S.C. § 1631 is reviewed for an
abuse of discretion).

                          CONCLUSION

   The district court properly dismissed OCE’s claims regard-
ing the manner and timing of review of the guidelines, the
scheduling of plan publication and identification of new pol-
luting sources, and did not abuse its discretion in refusing to
transfer OCE’s claims to this court.

  AFFIRMED. Each party shall bear its own costs on
appeal.
