                               In the

    United States Court of Appeals
                 For the Seventh Circuit
                     ____________________
No. 19-1130
MENOMINEE INDIAN TRIBE OF WISCONSIN,
                                                  Plaintiff-Appellant,
                                 v.

ENVIRONMENTAL PROTECTION AGENCY and UNITED STATES
ARMY CORPS OF ENGINEERS, et al.
                                Defendants-Appellees,

                                and

AQUILA RESOURCES, INC.,
                                   Intervening Defendant-Appellee.
                     ____________________

         Appeal from the United States District Court for the
                   Eastern District of Wisconsin.
          No. 1:18-cv-108 — William C. Griesbach, Judge.
                     ____________________

  ARGUED SEPTEMBER 5, 2019 — DECIDED JANUARY 27, 2020
                     ____________________

   Before SYKES, HAMILTON, and SCUDDER, Circuit Judges.
   SCUDDER, Circuit Judge. For the Menominee Indian Tribe,
the river that bears its name is a place of special importance.
2                                                   No. 19-1130

The Menominee River runs along the border between North-
ern Wisconsin and Michigan’s Upper Peninsula. According to
its origin story, the Tribe came into existence along the banks
of the River thousands of years ago. This birthplace contains
artifacts and sacred sites of historic and cultural importance
to the Tribe. All these years later, the Tribe returns to the
riverbanks for ceremonies and celebrations.
    Sometime before 2017, the Tribe learned that Aquila Re-
sources intended to embark on a mining project known as the
Back Forty alongside the Menominee River and in close prox-
imity to Wisconsin’s northeast border. Aquila successfully ap-
plied for several necessary permits from the state of Michigan.
Concerned the project would disrupt and dislocate aspects of
tribal life, the Tribe wrote letters to the Environmental Protec-
tion Agency and Army Corps of Engineers asking both agen-
cies to reconsider its 1984 decision to allow Michigan, instead
of the federal government, to issue certain permits under the
Clean Water Act. The EPA and Army Corps responded not by
revisiting the prior delegation of permitting authority but in-
stead by informing the Tribe of what it already knew—that
Michigan would decide whether to issue a so-called dredge-
and-ﬁll permit to authorize Aquila’s Back Forty project.
   The Tribe responded on two fronts—ﬁrst by commencing
an administrative proceeding in Michigan and second by ﬁl-
ing suit in federal court in Wisconsin. The district court dis-
missed the Tribe’s complaint on the ground that it did not
challenge any ﬁnal action taken by the EPA or Army Corps.
The court also denied the Tribe’s request to amend its com-
plaint. Despite reservations about how the federal agencies
responded to the Tribe’s concerns, we aﬃrm.
No. 19-1130                                                    3

                                I
    To open and operate the Back Forty mine, Aquila had to
acquire several regulatory permits. The focus here is on Aq-
uila’s need for a dredge-and-ﬁll permit, which comes under
Section 404 of the Clean Water Act, 33 U.S.C. § 1344, and al-
lows its holder to ﬁll wetlands.
    Section 404 regulation is not an entirely federal undertak-
ing. Although the EPA and Army Corps are tasked with en-
forcing the Clean Water Act, Congress allows states to apply
to assume Section 404 permitting authority over waters in
their jurisdictions. See 33 U.S.C. § 1344(g)–(h). Michigan is one
of only two states that has implemented a Section 404 permit
program. See 40 C.F.R. § 233.70 (codifying Michigan’s as-
sumption of dredge-and-ﬁll permitting over certain waters).
    When a state assumes permitting authority, the federal
government is not removed from the Section 404 regulatory
process altogether. The EPA maintains an oversight role re-
viewing state-proposed permits. See 33 U.S.C. § 1344(j). A
state may not issue a proposed permit if the EPA objects. See
id. The EPA and Corps also continue to hold regulatory au-
thority over waterways that ﬂow between states and can be
used for commercial activity, as Congress determined that
those waters cannot be delegated to state control. See id.
§ 1344(g)(1) (providing that federal agencies issue permits for
navigable waters—deﬁned as those waters used or suscepti-
ble to use in interstate commerce).
   Knowing that Michigan had received authority for
dredge-and-ﬁll permitting in 1984, Aquila directed its Section
404 application to Michigan’s Department of Environmental
Quality. The company’s application, and the Back Forty
4                                                  No. 19-1130

project more generally, concern the Menominee Tribe. The
Tribe fears that some of its sacred sites could be damaged by
changes to the River and increased activity on its banks. Tribal
members often go to the River’s banks to visit the burial
mounds of tribal ancestors and to perform and participate in
ceremonies. Recently the Tribe reports working to reestablish
wild rice at the mouth of the River to preserve and continue
its traditional agricultural practices. The Tribe also became of
the view that the recent growth of commercial activity on the
Menominee River meant that the federal government, not
Michigan, should be in charge of permitting.
    In August 2017 the Tribe expressed its concerns in letters
to the EPA and Army Corps. The Tribe acknowledged that
under the 1984 agreement between the EPA and Michigan, the
state took over issuance of dredge-and-ﬁll permits for many
of the state’s waterways, subject to the EPA’s oversight pre-
served in the Clean Water Act. See 33 U.S.C. § 1344(j). But the
Tribe emphasized that circumstances had changed since the
1984 delegation. In the past 35 years, the Tribe explained, the
Menominee River had experienced a growth of commercial
activity, including riverboat tourism. This commercial activ-
ity, the Tribe continued, had a legal consequence: the segment
of the Menominee River nearest to the proposed Back Forty
mining site constituted a navigable waterway within the
meaning of the Clean Water Act and therefore permitting for
it could not remain delegated to the state. The Tribe asked the
EPA and Corps to revisit whether they—as opposed to the
state of Michigan—should exercise authority over Aquila’s
Back Forty permit application. At the very least, the Tribe
sought to consult with the EPA and Corps before Michigan
made any decision about the Back Forty project.
No. 19-1130                                                   5

    Who decides the permitting question matters greatly to
the Tribe, and for good reason. The Tribe sought to negotiate
directly with the federal government because the United
States has a long-recognized general trust responsibility to-
ward Native Americans. See Seminole Nation v. United States,
316 U.S. 286, 297 (1942) (explaining government’s “moral ob-
ligations of the highest responsibility and trust” toward In-
dian communities); see also United States v. Mitchell, 463 U.S.
206, 225–26 (1983) (emphasizing the same point).
    The Tribe also saw speciﬁc procedural and legal beneﬁts
to the dredge-and-ﬁll permit being decided by the federal
agencies. If the permitting had been handled in the federal
system, the Tribe would have enjoyed more participation
rights. For example, the National Environmental Policy Act
would have applied and likely required the EPA to complete
an environmental assessment or impact statement about the
Back Forty mine. See 42 U.S.C. § 4332(C); 40 C.F.R. §§ 1501.3,
1501.4. Through that process, the Tribe would have an oppor-
tunity to request consultation with federal environmental of-
ﬁcials. See 40 C.F.R. §§ 1501.2(d)(2), 1501.7(a)(1).
   The agencies responded by reinforcing—but not revisit-
ing—the 1984 delegation. For its part, the Corps explained
that it could not exercise jurisdiction over the permitting pro-
cess for the Back Forty mine because permitting for the rele-
vant section of the Menominee River had been assumed by
Michigan in 1984. One month later, the Tribe received a six-
sentence letter from the EPA not at all addressing its concerns
but oﬀering to speak with the Tribe by phone. Neither re-
sponse addressed the Tribe’s request for the agencies to re-
consider whether changed circumstances warranted the re-
newed exercise of federal authority over the relevant section
6                                                   No. 19-1130

of the Menominee River. Taking those letters as non-respon-
sive, the Tribe turned to the courts and ﬁled this lawsuit in the
Eastern District of Wisconsin, naming the EPA, Army Corps,
and the agencies’ secretaries as defendants.
   The federal lawsuit did not proceed very far. Aquila inter-
vened in the action and joined the agencies in moving under
Federal Rule of Civil Procedure 12(b)(1) and (6) to dismiss the
Tribe’s complaint. The district court granted the motion on
the basis that the challenged EPA and Army Corps letters
were not “ﬁnal agency actions” within the meaning of Section
704 of the Administrative Procedure Act and therefore were
not subject to judicial review.
    At the same time, the Michigan Department of Environ-
mental Quality continued processing Aquila’s Section 404
permit application. As required under its agreement with the
EPA, Michigan submitted its proposed dredge-and-ﬁll permit
for Aquila’s mine to the EPA for federal review. The EPA ob-
jected to the permit and asked Michigan for additional infor-
mation. A few months later, the state submitted a new draft
permit. Upon reviewing the new draft and Michigan’s re-
sponses, the EPA withdrew its prior objections on the basis
that its concerns had been alleviated. More speciﬁcally, the
EPA allowed permitting to proceed if certain conditions were
included in the ﬁnal state permit. The state complied and
granted Aquila the permit in June 2018. Shortly thereafter the
Tribe challenged the permit in Michigan’s administrative sys-
tem. That case is still pending.
                               II
   This appeal presents two questions—one narrow and one
broad. The ﬁrst is whether the agency action here is judicially
No. 19-1130                                                    7

reviewable. The broader question asks what legal avenue is
available for the Tribe to seek review of the state delegation of
the permitting process for the part of the Menominee River
aﬀected by the Back Forty project in light of changed circum-
stances.
                               A
    We begin with the narrow question, which returns us to
the Tribe’s complaint. The Tribe invoked the Administrative
Procedure Act and alleged that the federal agencies’ decision
not to exercise permitting authority over the dredge-and-ﬁll
permit for the Back Forty project was arbitrary and capricious
and contrary to law. See 5 U.S.C. § 702. The district court con-
cluded that it lacked authority to review that question be-
cause it was not a “ﬁnal agency action” within the meaning of
the APA.
    The APA limits judicial review to “ﬁnal agency action[s].”
5 U.S.C. § 704. The Supreme Court has explained that to con-
stitute a ﬁnal action, the decision in question “must mark the
consummation of the agency’s decisionmaking process—it
must not be of a merely tentative or interlocutory nature” and
it must “be one by which rights or obligations have been de-
termined, or from which legal consequences will ﬂow.” Ben-
nett v. Spear, 520 U.S. 154, 177–78 (1997) (internal quotations
omitted).
    The district court applied this framework and concluded
that the EPA and Army Corps’s letters did not reﬂect any ﬁnal
agency decisions. We agree. The EPA and Corps’s responses
did little but restate what the Tribe already knew—that Mich-
igan, as a result of the 1984 delegation, had permitting author-
ity over the section of the Menominee River near the Back
8                                                     No. 19-1130

Forty site. A letter “purely informational in nature” is not a
ﬁnal agency action because it “impose[s] no obligations and
denie[s] no relief.” See Indep. Equip. Dealers Ass'n v. EPA, 372
F.3d 420, 427 (D.C. Cir. 2004). Letters restating earlier inter-
pretations likewise do not carry legal consequences for pur-
poses of the “ﬁnal agency action” requirement. See Clayton
County v. Fed. Aviation Admin., 887 F.3d 1262, 1268 (11th Cir.
2018). Because the Corps and EPA letters only reiterated the
status quo, there was nothing for the district court (or now,
us) to review.
    The Tribe understandably will ﬁnd this conclusion unset-
tling. Its letters to the EPA and the Army Corps were detailed
and speciﬁc. The Tribe explained its basis for believing that
the relevant part of the Menominee River should be under
federal permitting authority. Neither the EPA nor the Corps
accepted the Tribe’s invitation to revisit the 1984 delegation
decision in light of the changed commercial circumstances
highlighted in the Tribe’s letters. Indeed, neither agency re-
sponded in any way to that contention. This silence is partic-
ularly troubling since the agencies asserted for the ﬁrst time
at oral argument that the Tribe could have sought the re-
quested relief by ﬁling a petition for rulemaking under 5
U.S.C. § 553(e). We are at a loss to understand why the EPA
and the Army Corps did not inform the Tribe of this route
upon receiving its letters.
   Although we see nothing standing in the way of the
Tribe’s ability to ﬁle a § 553(e) petition at this point, it may be
too late for any rulemaking to aﬀect the dredge-and-ﬁll per-
mit at issue in this case. This further adds to our sense that the
Tribe got the runaround here.
No. 19-1130                                                     9

                                B
    Even if we could somehow treat the agency responses as
reﬂecting ﬁnal decisions, our next step would be far from
clear given parallel proceedings ongoing in Michigan. In ad-
dition to ﬁling suit in federal court, the Tribe contested Aq-
uila’s Section 404 permit before the Michigan Department of
Environmental Quality. To our knowledge that proceeding
(which is called a contested case hearing) is pending before
Michigan’s Administrative Hearing System. See MICH.
ADMIN. CODE r. 792.10301–.10306. And, if it does not prevail,
the Tribe can seek review of the outcome of the contested case
hearing in state court. See MICH. COMP. LAWS §§ 24.302–.305.
    Duplicative litigation in state and federal courts can cause
coordination problems, interfere with eﬀective government
functioning, and lead to conﬂicting judgments. See, e.g., Colo-
rado River Water Cons. Dist. v. United States, 424 U.S. 800, 817
(1976). The Tribe sees those concerns as overstated because it
perceives the scope of the state proceedings to be narrow. It
says that there will be no overlap between the state and fed-
eral suits because the state administrative proceeding will not
entail an adjudication of Michigan’s dredge-and-ﬁll permit-
ting authority under the Clean Water Act. For support, it notes
that in denying a motion for a stay, the administrative law
judge ruled on only state-law grounds.
    But the administrative law judge has not yet reached a de-
cision on the merits, and after that the Tribe may turn to the
state court for relief. As the Tribe acknowledged in its letter to
the EPA and the Corps, the deﬁnition of “navigability” is ul-
timately decided by the judiciary. See 33 C.F.R. § 329.3. The
ultimate decider need not be the federal judiciary, though.
State courts are equally able to adjudicate questions of federal
10                                                  No. 19-1130

law. See Taﬄin v. Levitt, 493 U.S. 455, 459 (1990) (noting the
“deeply rooted presumption” of concurrent jurisdiction over
cases arising under federal law unless Congress decides oth-
erwise). It is not the unique province of the federal courts to
adjudicate administrative law challenges related to the Clean
Water Act. See, e.g., In re Freshwater Wetlands Prot. Act Rules,
798 A.2d 634, 643 (N.J. Super. Ct. App. Div. 2002) (evaluating
whether state 404 permit met federal standards); see also Si-
erra Club Mackinac Chapter v. Dep’t of Envtl. Quality, 747
N.W.2d 321, 331–32, 335 (Mich. App. 2008) (concluding that
pollution-discharge permit violated the Clean Water Act).
Nothing has been brought to our attention to suggest that the
Tribe cannot receive full and fair review in a Michigan court.
                               III
    The Tribe also challenges the district court’s denial of its
motion for leave to amend its complaint. The Tribe sought to
add two Administrative Procedure Act claims—one contend-
ing that the EPA’s withdrawal of its objections to Michigan’s
issuance of the permit was arbitrary and capricious, and a sec-
ond alleging that the agencies failed to consult with the Tribe
about the Back Forty mine as Congress required under the
National Historic Preservation Act. The district court denied
the motion on the basis of futility, reasoning that neither claim
would survive a motion to dismiss. We review a denial of a
motion for leave to amend for abuse of discretion, while con-
sidering any embedded legal questions de novo. See Gandhi v.
Sitara Capital Mgmt., LLC, 721 F.3d 865, 868–69 (7th Cir. 2013).
                               A
   To evaluate the Tribe’s claim that the EPA’s withdrawal of
objections to Michigan’s proposed permit was arbitrary and
No. 19-1130                                                  11

capricious, we must revisit the regulatory scheme. Recall that
where Section 404 permitting authority has been delegated to
a state, the EPA retains an oversight role. See 33 U.S.C.
§ 1344(j). The EPA reviews, and can object to, proposed per-
mits. See id. If the agency lodges objections, the state cannot
issue a permit without revising and resubmitting it for ap-
proval. See id.; see also 40 C.F.R. § 233.50.
    The EPA originally objected to Michigan’s proposed
dredge-and-ﬁll permit for Aquila’s Back Forty project on mul-
tiple grounds and sought more information. Michigan sub-
mitted a revised permit and agreed to add additional condi-
tions, including, for example, a requirement that Aquila mon-
itor the eﬀect of dust levels on nearby wetlands. Upon its sec-
ond review, EPA concluded that its concerns were resolved
and allowed the permit to go forward.
    In the district court, the Tribe sought leave to amend its
complaint to challenge the EPA’s withdrawal of its objections
to the permit that Michigan planned to issue to Aquila. The
Tribe asserts that the EPA provided little to no explanation,
rendering its decision arbitrary and unsupported. The district
court, however, concluded that the proposed claim would fail
(and therefore be futile) because the EPA’s decision was ex-
empt from judicial review as a matter of law. Speciﬁcally, the
district court reasoned that the EPA’s decision to withdraw its
objections was “committed to agency discretion by law.” 5
U.S.C. § 701(a)(2).
    The Supreme Court has explained that § 701’s limitation
on judicial review is “a very narrow exception” applicable
only when there is “no law to apply.” Citizens to Preserve Over-
ton Park, Inc. v. Volpe, 401 U.S. 402, 410 (1971). Discretionary
enforcement decisions reﬂect one category of agency
12                                                    No. 19-1130

decisions that the Supreme Court has identiﬁed as unsuitable
for judicial review. A clear illustration came in Heckler v.
Cheney, 470 U.S. 821 (1985). There the Court explained that
courts generally do not review agency decisions about
whether to bring an enforcement action because such a deci-
sion “often involves a complicated balancing of a number of
factors which are peculiarly within its expertise.” Id. at 831.
Such factors, the Court underscored, include resource con-
straints and policy priorities. See id.
    When deciding whether a decision is committed to agency
discretion, we ﬁrst review the applicable statutes and regula-
tions. See Head Start Family Educ. Program, Inc. v. Coop. Educ.
Serv. Agency 11, 46 F.3d 629, 632 (7th Cir. 1995). We examine
those measures to see if they contain “judicially manageable
standards . . . for judging how and when an agency should
exercise its discretion.” Heckler, 470 U.S. at 830; see also Miami
Nation of Indians of Ind. v. Dept. of Interior, 255 F.3d 342, 348–49
(7th Cir. 2001) (examining regulations governing the tribal
recognition process to determine if they contain criteria that
“courts are capable of applying”).
    The Tribe does not point to any regulations governing the
withdrawal of objections. We searched too and came up
empty, ﬁnding no statute, regulation, or guideline that in-
structs the EPA how to decide whether a state has tendered a
satisfactory resolution to a previous permitting objection. The
Tribe suggests that we ﬁll the gap by looking to the regula-
tions governing the decision to object in the ﬁrst place. It notes
that those regulations require that any objection “be based on
the [EPA’s] determination” that the proposed permit is “out-
side [the] requirements of the [Clean Water] Act, these regu-
lations, or the 404(b)(1) Guidelines.” 40 C.F.R. § 233.50(e). On
No. 19-1130                                                    13

the surface, the Tribe’s argument makes sound sense: the
same reasons that the EPA might object could, the reasoning
runs, be used to decide when a permit can go forward.
    We read the regulatory language another way, though. Re-
member that the language about objections is permissive,
making plain that “[a]ny such objection” the EPA chooses to
lodge must be based on certain prescribed factors. Id. The in-
itial choice—the decision whether to object—remains discre-
tionary. That discretion remains no matter how much a par-
ticular permitting proposal may, as an objective matter, devi-
ate from the prescribed regulatory standards. See id.; see also
Heckler, 470 U.S. at 835–37 (explaining that agency action was
unreviewable where nothing in the regulatory scheme com-
pelled enforcement in the event of violations); American Paper
Inst. v. EPA, 890 F.2d 869, 878 (7th Cir. 1989) (concluding that
the EPA’s decision to object to a state-issued permit in a simi-
larly structured pollutant-discharge program under the Clean
Water Act was committed to agency discretion).
    The proper conclusion, then, is that, in the absence of any
regulation addressing the basis for the decision to withdraw
an objection, the choice is as committed to the agency’s dis-
cretion as the decision to object in the ﬁrst instance. If the EPA
ﬁnds a shortcoming in the state’s response to a particular ob-
jection, the agency must again make a judgment call about
whether to maintain the objection. The decision may depend
on many factors, including the EPA’s judgment about not
only the materiality of the concern that gave rise to the initial
objection and the suﬃciency of the state’s responsive
measures, but also whether the agency’s limited time and re-
sources are best used to persist with an objection pertinent to
one project when others likewise call for federal attention.
14                                                    No. 19-1130

    The Tribe would be on much stronger footing if the Clean
Water Act’s regulatory scheme required the EPA to object if
certain conditions were not met. See, e.g., Amador County v.
Salazar, 640 F.3d 373, 376–77 (D.C. Cir. 2011) (rejecting the ar-
gument that the Secretary of the Interior’s acceptance of a
state-tribal compact was committed to agency discretion be-
cause the law at issue obligated the Secretary to disapprove of
compacts that violated the regulatory scheme). But the diﬀer-
ence in the Section 404 context—that the agency is not com-
pelled to address all defects in every proposed dredge-and-
ﬁll permit—is that the withdrawal decision is committed to
the EPA’s discretion. And it is that reality that requires us to
reject the Tribe’s proposed claim.
    A ﬁnal and broader point is worth observing. The Clean
Water Act’s regulations allow the EPA to decline to review
whole categories of state-issued dredge-and-ﬁll permits
through a blanket waiver program. See 40 C.F.R. § 233.51; see
also Save the Bay, Inc. v. EPA, 556 F.2d 1282, 1295 (5th Cir. 1977)
(noting similar feature of the Clean Water Act pollutant dis-
charge program as support for concluding that EPA decision
not to veto a permit was committed to agency discretion and
therefore not subject to judicial review). It makes little sense
to apply a strict set of criteria for withdrawing objections
when the regulatory scheme allows the EPA to assign whole-
sale its review authority and put permitting completely in the
hands of the state oﬃcials. That expansive delegation author-
ity reinforces our conclusion that the Clean Water Act com-
mits dredge-and-ﬁll permit objections and subsequent with-
drawals to the EPA’s discretion.
No. 19-1130                                                  15

                               B
    The Tribe also sought leave to add another APA claim—
that the EPA had failed to recognize the Tribe’s consultation
rights conferred by the National Historical Preservation Act.
See 5 U.S.C. § 706(1) (authorizing courts to “compel agency
action unlawfully withheld or unreasonably delayed”). The
Preservation Act creates a consultation requirement for cer-
tain federal “undertaking[s].” 54 U.S.C. § 306108. The federal
agency overseeing the project must, before approving fund-
ing or licensure, “take into account the eﬀect of the undertak-
ing on any historic property.” Id. The Preservation Act em-
phasizes the importance of protecting the interests of recog-
nized Indian tribes and requires consultation when an under-
taking would alter historic property of religious or cultural
signiﬁcance to a tribe. See id. §§ 302701, 306102(b)(5)(B).
    The Tribe reads the Preservation Act as obligating the EPA
and Army Corps to consult with it about the Back Forty mine
project. But that position is mistaken. The Preservation Act
applies only to undertakings that are “[f]ederal or federally
assisted.” Id. § 306108. The Tribe alleged neither federal fund-
ing nor federal assistance. We have held that the procedural
requirements of the statute do not apply to projects for which
no federal support has been sought, “no federal dollars have
been obligated, and no federal license is required.” Old Town
Neighborhood Ass'n Inc. v. Kauﬀman, 333 F.3d 732, 735 (7th Cir.
2003). Because the Back Forty mine is privately funded and
state-licensed, the Preservation Act’s consultation require-
ment is not triggered here.
16                                                  No. 19-1130

                              ***
    The Menominee Indian Tribe of Wisconsin’s sincere ef-
forts to protect its cultural heritage ran into a legal labyrinth
and regulatory misdirection. Had the federal agencies pro-
vided a meaningful response to the Tribe’s concerns, perhaps
this suit could have been avoided. But in light of the regula-
tory scheme that we cannot change, the resolution of this case
is clear. We cannot review the agency action here. In these cir-
cumstances, the Tribe is left to pursue its challenge in the
Michigan administrative system and state courts. And we are
left to AFFIRM the judgment of the district court.
No. 19-1130                                                     17

    HAMILTON, Circuit Judge, concurring. I agree that the EPA
and Army Corps letters were not final agency actions, 5 U.S.C.
§ 704, and that the EPA’s decision to withdraw its objections
to the Michigan permit was committed to agency discretion
by law, id. § 701(a)(2). As a result, the federal courts lack au-
thority to intervene in this dispute at this juncture. I write sep-
arately (a) to highlight the problem with the statutory stand-
ard that allows the federal government to delegate Clean Wa-
ter Act permitting to the State of Michigan and (b) to empha-
size that the Tribe can still pursue its challenges to the Back
Forty mine under Section 404 of the Act, 33 U.S.C. § 1344,
through the EPA and the Michigan state courts.
    A delegation of Clean Water Act permitting authority to a
state under 33 U.S.C. § 1344(g) must, as a practical matter, re-
flect a fairly long-term commitment. The practical problem
with the statutory standard is that the state’s permissible ju-
risdiction over waters depends on facts that can change over
time. The delegation may not include major waterways,
though. The statute bars delegation for “waters which are
presently used, or are susceptible to use in their natural con-
dition or by reasonable improvement as a means to transport
interstate or foreign commerce shoreward to their ordinary
high water mark” and adjacent wetlands. 33 U.S.C.
§ 1344(g)(1). Under this standard, as uses of particular
stretches of waterways may change, so may the legality of a
federal delegation of authority to a state. As applied to the
Menominee River near the proposed Back Forty mine, there
is a substantial issue whether the original delegation in 1984
remains valid as a matter of federal law.
18                                                    No. 19-1130

    That issue is not teed up for federal courts to decide in this
case, as Judge Scudder has explained. That does not mean the
issue is closed, however.
    First, the Tribe may petition the EPA to reassume federal
permitting authority over this stretch of the Menominee River
as an amendment to a rule. See 5 U.S.C. § 553(e). The EPA’s
1984 approval of Michigan’s Section 404 permit program bore
the hallmarks of a legislative rule. See 49 Fed. Reg. 38,947 (Oct.
2, 1984), codified at 40 C.F.R. § 233.70. The approval was writ-
ten as a “regulation” that was promulgated after public notice
and comment. See id. at 38,947; see also 40 C.F.R. § 233.15(e)
(providing for public participation in state program approv-
als). The EPA would have a duty to respond to any petition
for revisions to the scope of the Michigan delegation. See Nat’l
Parks Conservation Ass’n v. U.S. Dep’t of Interior, 794 F. Supp.
2d 39, 44 (D.D.C. 2011) (“an agency ‘is required to at least de-
finitively respond to . . . [a] petition—that is, to either deny or
grant the petition” (alteration in original)).
    If the Tribe submits such a petition, the EPA will have to
answer within a reasonable time. See 5 U.S.C. § 555(b) (requir-
ing an agency to “conclude a matter presented to it” within “a
reasonable time”); id. § 706(1) (a “reviewing court shall . . .
compel agency action unlawfully withheld or unreasonably
delayed”); see also Envtl. Integrity Project v. EPA, 160 F. Supp.
3d 50, 54 (D.D.C. 2015) (“the APA is the source of an agency’s
duty to respond to a petition for rulemaking . . . within a rea-
sonable time . . . .”); Families for Freedom v. Napolitano, 628 F.
Supp. 2d 535, 540 (S.D.N.Y. 2009) (holding that delay in de-
ciding a rulemaking petition was unreasonable and ordering
response within thirty days). The D.C. Circuit has set forth a
general framework for deciding claims of agency delay that
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courts can apply to unanswered rulemaking petitions. See Tel-
ecommunications Research & Action Ctr. v. FCC, 750 F.2d 70, 80
(D.C. Cir. 1984) (identifying six factors to evaluate); Families
for Freedom, 628 F. Supp. 2d at 540 (applying TRAC factors in
this context).
    Absent periodic review by the EPA, the scope of a Section
404 delegation to a state could quickly fall behind the times
and out of legal compliance. This case illustrates that risk. As
codified, the Michigan approval incorporated a Memoran-
dum of Agreement signed in the spring of 1984 that retained
just a small portion of the Menominee River under federal ju-
risdiction. See 40 C.F.R. § 233.70(c)(2); Joint App. at 163, 166,
168. But rivers change, and so does the commerce they carry.
The nearly forty-year-old memorandum might no longer re-
flect actual conditions. The EPA may need to decide, on its
own initiative or in response a petition by the Tribe, whether
the 1984 delegation is still viable as applied to the Menominee
River near the Back Forty mine.
    A reassessment by the EPA to ensure that the scope of the
Michigan delegation still complies with the Clean Water Act
appears long overdue. I don’t mean to criticize § 1344(g)(1);
the statute reflects policy compromises that are of course up
to Congress. But since Congress chose to make the scope of
permissible delegation depend on circumstances that can
change decisively over time, agencies and courts must do
their best to comply. The Act also provides that the EPA
“shall” withdraw approval of a state program not adminis-
tered “in accordance with this section,” including the jurisdic-
tional provision. 33 U.S.C. § 1344(i). I express no view on
whether or how such a withdrawal would aﬀect current con-
troversies like this case.
20                                                   No. 19-1130

    Second, as Judge Scudder’s opinion for the panel observes,
the Tribe may argue in state court that Michigan lacks permit-
ting jurisdiction over this portion of the Menominee River un-
der § 1344(g)(1). If the Tribe raises that issue of federal law, a
state court will need to decide it. Michigan courts have heard
Clean Water Act challenges to state actions. See Sierra Club
Mackinac Chapter v. Dep’t of Envtl. Quality, 747 N.W.2d 321,
331–32, 335 (Mich. App. 2008) (ruling that Michigan courts
had jurisdiction over claim that general permit violated the
Clean Water Act and finding such a violation). If the Tribe
were to prevail in state court on its jurisdictional argument,
such a decision would deprive Michigan environmental oﬃ-
cials of “adequate authority to carry out” the state program
on this stretch of river. 33 U.S.C. § 1344(g)(1). That decision
would presumably require the EPA to reassume federal au-
thority, exercising its power under § 1344(i) if necessary.
    The Tribe objects that the Michigan administrative law
judge who is hearing the “contested case” has refused to ad-
dress the questions of federal law, including a challenge to the
scope of the federal delegation of permitting authority. See
Order on Motion to Stay, Petitions of Thomas Boerner et al., No.
18-013058 at 2–3 (Mich. Admin. Hearing Sys. Jan. 29, 2019) (at-
tached to Appellant’s Br.). I express no view on the adminis-
trative law judge’s refusal to consider the scope of the delega-
tion as a matter of Michigan administrative law, but limits on
the issues that administrative law judges may consider are not
unusual. Whether the administrative law judge is right or
wrong, however, should not aﬀect the power of Michigan
courts of general jurisdiction to address the issue.
   If the Tribe seeks judicial review in a Michigan circuit
court, see Mich. Comp. Laws §§ 24.302–.305, that court will be
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bound to examine a jurisdictional challenge based on federal
law. “State courts, like federal courts, have a constitutional
obligation to safeguard personal liberties and to uphold fed-
eral law.” Stone v. Powell, 428 U.S. 465, 494 n.35 (1976); Martin
v. Hunter’s Lessee, 14 U.S. (1 Wheat.) 304, 340–44 (1816) (Su-
premacy Clause requires both federal and state judges to de-
cide cases “according to the constitution, laws and treaties of
the United States”); see also Gulf Oﬀshore Co. v. Mobil Oil Corp.,
453 U.S. 473, 477–78 (1981) (recognizing state courts’ duty to
apply binding federal law). If the state courts reject the Tribe’s
arguments under federal law, review would ultimately lie
with the Supreme Court under 28 U.S.C. § 1257.
    For now, however, the EPA’s 1984 delegation of authority
over this stretch of the Menominee River to Michigan remains
in eﬀect. For that reason, we must aﬃrm. The Tribe must ask
the EPA, the Michigan ALJ, and Michigan courts to examine
alleged infirmities in the Section 404 permit for the mine.
