                 FOR PUBLICATION

  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT


NORTHERN ALASKA                          No. 19-35008
ENVIRONMENTAL CENTER; ALASKA
WILDERNESS LEAGUE; DEFENDERS                D.C. No.
OF WILDLIFE; SIERRA CLUB; THE            3:18-cv-00030-
WILDERNESS SOCIETY, INC.,                     SLG
               Plaintiffs-Appellants,

                  v.                       OPINION

U.S. DEPARTMENT OF THE INTERIOR;
BUREAU OF LAND MANAGEMENT;
DAVID L. BERNHARDT, in his official
capacity as Secretary of the Interior;
BRIAN STEED, in his official capacity
as the official exercising the
authority of the Director of the
Bureau of Land Management,
                 Defendants-Appellees,

CONOCOPHILLIPS ALASKA, INC.,
           Intervenor-Defendant-
                        Appellee.

      Appeal from the United States District Court
               for the District of Alaska
      Sharon L. Gleason, District Judge, Presiding

        Argued and Submitted February 7, 2020
                 Seattle, Washington
2                        NAEC V. USDOI

                        Filed July 9, 2020

Before: MILAN D. SMITH, JR. and N. RANDY SMITH,
 CIRCUIT JUDGES, and JOHN R. TUNHEIM, * District
                     Judge.

             Opinion by Judge Milan D. Smith, Jr.


                          SUMMARY **


                      Environmental Law

    The panel affirmed the district court’s summary
judgment in favor of federal agencies and officials and
intervenor ConocoPhillips Alaska, Inc. in a National
Environmental Policy Act (“NEPA”) action brought by
environmental groups challenging the Bureau of Land
Management (“BLM”)’s 2017 offer and sale of oil and gas
leases in the National Petroleum Reserve-Alaska (the
Reserve).

    In 2012, BLM published a document styled as a
combined Integrated Activity Plan (“IAP”) and
Environmental Impact Statement (“EIS”), designed to
determine the appropriate management of all BLM-managed
lands in the Reserve. In 2017, BLM issued a call for


    *
      The Honorable John R. Tunheim, United States Chief District
Judge for the District of Minnesota, sitting by designation.
    **
       This summary constitutes no part of the opinion of the court. It
has been prepared by court staff for the convenience of the reader.
                      NAEC V. USDOI                           3

nominations and comments on all unleased tracts for the
2017 lease sale.

     The panel first held that, to the extent plaintiffs argued
that the 2017 lease sale was a distinct federal action requiring
a tiered or standalone NEPA analysis, their claims were not
barred by the Naval Petroleum Reserves Production Act 60-
day limitations period applicable to the 2012 EIS.

    The panel agreed with the environmental groups that the
2017 lease sale required some form of site-specific analysis,
but found that the instant dispute was whether the required
analysis had already been prepared. The panel held that the
fact that the 2012 EIS provided a programmatic-level
analysis for the IAP did not preclude the legal possibility that
it also served as the necessary site-specific analysis for
future lease sales. The panel also was not persuaded that the
degree of site specificity required for the 2017 lease sale was
so clearly greater than that reflected in the 2012 EIS that the
2012 EIS could not have covered the 2017 lease sale.

    The panel declined to inquire whether the 2012 EIS
adequately analyzed the impacts of the 2017 lease sale,
finding that this approach would rob the statute of limitations
of effect in situations where some steps of a previously
studied action remain to occur after expiration of the
limitations period. The panel also declined to inquire
whether the 2017 lease sale was in conformity with the IAP,
finding that this approach fails to account for whether
members of the public have fair notice of when they should
challenge the NEPA compliance of a particular action.

    Instead, the panel inquired whether the 2012 EIS
purported to be the EIS for the 2017 lease sale, as reflected
in the 2012 EIS’ defined scope. The panel concluded that
4                    NAEC V. USDOI

the expressly defined scope of the 2012 EIS was somewhat
ambiguous as to this question, but that the language
regarding future NEPA requirements provided reasonable
notice that the intended scope encompassed actual future
lease sales. The panel also found that construing the scope
of the 2012 EIS as such was not unreasonable when
considering the analysis performed therein and the
applicable law. Thus, the panel deferred to BLM’s
reasonable position that the 2012 EIS was the EIS for the
2017 lease sale.

     The panel therefore held that BLM met the NEPA
requirement for the 2017 lease sale of preparing at least an
initial EIS, any challenge to the adequacy of which is now
time barred. Although plaintiffs alleged significant new
information and circumstances known to BLM before the
2017 lease sale, the appropriate rubric for considering these
allegations—given the existence of an initial EIS—was
supplementation, and plaintiffs waived any supplementation
claim.


                        COUNSEL

Suzanne Bostrom (argued), Brook Brisson, and Valerie
Brown, Trustees for Alaska, Anchorage, Alaska, for
Plaintiffs-Appellants.

Thekla Hansen-Young (argued), John David Gunter II, and
Romney S. Philpott, Attorneys; Eric Grant, Deputy Assistant
Attorney General; Jeffrey Bossert Clark, Assistant Attorney
General; Environment and Natural Resources Division,
United States Department of Justice, Washington, D.C.;
Michael Gieryic, Attorney-Advisor, Office of the Solicitor,
                         NAEC V. USDOI                                5

United States Department of the Interior, Washington, D.C.;
for Defendants-Appellees.

Ryan P. Steen (argued) and Jason T. Morgan, Stoel Rives
LLP, Seattle, Washington, for Intervenor-Defendant-
Appellee.


                             OPINION

M. SMITH, Circuit Judge:

    Northern Alaska Environmental Center (NAEC), Alaska
Wilderness League, Defenders Of Wildlife, Sierra Club, and
The Wilderness Society, Inc. (collectively, Plaintiffs),
appeal the district court’s grant of summary judgment for the
U.S. Department of the Interior, the Bureau of Land
Management (BLM), Secretary of the Interior Ryan Zinke, 1
and BLM Director Brian Steed (collectively, Federal
Defendants),      as     well      as   Intervenor-Defendant
ConocoPhillips Alaska, Inc. (collectively, Defendants).
Plaintiffs assert claims under the National Environmental
Policy Act (NEPA), 42 U.S.C. § 4321 et seq., and the
Administrative Procedure Act (APA), 5 U.S.C. § 706(2), on
the theory that BLM failed to prepare a required NEPA
analysis for its 2017 offer and sale of oil and gas leases (the
2017 lease sale) in the National Petroleum Reserve-Alaska
(the Reserve). Defendants contend that BLM conducted the
requisite NEPA analysis in an Environmental Impact
Statement (EIS) prepared in 2012. Defendants also claim
that, because any challenge to the adequacy of the 2012 EIS
is subject to a 60-day statute of limitations pursuant to the

    1
      This appeal substitutes current Secretary of the Interior David L.
Bernhardt.
6                     NAEC V. USDOI

Naval Petroleum Reserves Production Act (NPRPA),
42 U.S.C. § 6506a(n)(1), Plaintiffs’ claims are time barred.

     Finding that the NPRPA statute of limitations does not
bar our inquiry, we analyze the scope of the 2012 EIS and
ultimately defer to BLM’s position that the scope of the 2012
EIS encompassed future lease sales. We therefore find that
BLM met the NEPA requirement for the 2017 lease sale of
preparing at least an initial EIS, any challenge to the
adequacy of which is now time barred. Although Plaintiffs
allege significant new information and circumstances known
to BLM before the 2017 lease sale, the appropriate rubric for
considering these allegations—given the existence of an
initial EIS—is supplementation, and Plaintiffs have waived
any supplementation claim.

   Accordingly, we affirm the district court’s grant of
summary judgment for Defendants on all counts.

    FACTUAL AND PROCEDURAL BACKGROUND

    The Reserve comprises over 23 million acres of land
located along the north coast of Alaska, an area roughly the
size of Indiana. This vast expanse of Arctic tundra provides
habitat for polar bears, grizzly bears, gray wolves, moose,
caribou, and dozens of species of migratory birds. It is home
to numerous Native Alaskan communities that practice a
subsistence way of life, relying on the biological resources
of the Reserve. It is also a significant source of oil and gas.
As of 2017, the U.S. Geological Survey (USGS) estimated
that technically recoverable petroleum resources underlying
the Reserve include 8.7 billion barrels of oil and 25 trillion
cubic feet of natural gas.

   BLM manages 22.6 million acres of the Reserve
pursuant to the NPRPA, 42 U.S.C. §§ 6501–07. The
                         NAEC V. USDOI                               7

NPRPA directs BLM to lease Reserve land to private entities
for oil and gas development, while taking such measures as
BLM deems necessary or appropriate to mitigate adverse
environmental impacts. 42 U.S.C. § 6506a. BLM’s actions
taken pursuant to the authority of NPRPA are also subject to
NEPA procedural requirements for the analysis of potential
environmental impacts and reasonable alternatives. See
42 U.S.C. § 4332(2)(C).

I. The 2012 Environmental Impact Statement

    In 2012, BLM published a 2,600-page document styled
as a combined Integrated Activity Plan (IAP) and EIS,
designed to determine the appropriate management of all
BLM-managed lands in the Reserve. 2 The IAP/EIS
analyzed five alternative proposals for a range of land
allocations, including different options for the percentage of
lands that would be made available for oil and gas leasing.
The alternatives also included stipulations and required
operating procedures or best management practices to
mitigate environmental impacts. The IAP/EIS designated as
its preferred alternative a proposal that would make
approximately 52% of the federal lands in the Reserve
available for oil and gas leasing.

    In order to analyze the environmental consequences of
the various alternatives, BLM developed a set of
hypothetical development scenarios based on assumptions it
considered reasonable, seeking to minimize the chance that
its analysis would underestimate potential impacts. BLM

    2
      Hereinafter, we refer to this document generally as the IAP/EIS.
However, when we reference this document specifically in its NEPA
capacity, we refer to the 2012 EIS. When we reference this document
specifically in its land management plan capacity, we refer to the IAP.
8                       NAEC V. USDOI

assumed that multiple annual lease sales would be held, each
of which might offer all or only part of the lands made
available for oil and gas leasing, and that the industry would
need time to evaluate existing leases before actually leasing
additional tracts. BLM assumed that full exploration and
development of petroleum resources in the Reserve would
take place over many decades. Based on the then-most
recent USGS estimates, BLM assumed that the Reserve
contained 896 million barrels of technically recoverable oil,
604 million barrels of which were economically recoverable.

    The IAP/EIS predicted that it would fully satisfy
NEPA’s requirements for the first oil and gas lease sale.
With respect to anticipated subsequent lease sales, it stated
that BLM would prepare an administrative determination of
NEPA adequacy (DNA) in connection with each proposed
lease to determine whether the then-existing NEPA
documentation was adequate. 3

    In 2013, BLM published a Record of Decision that
finalized its decision to manage the Reserve under the
preferred alternative. Each year thereafter, through 2016,
BLM offered oil and gas leases on 1–2 million acres of the
Reserve, but ultimately sold leases on only a small portion
of the offered acreage. In conjunction with each offering,
BLM prepared a four-page DNA documenting its conclusion
that the 2012 EIS remained adequate to meet the
requirements of NEPA, so no further NEPA documentation
was required to support the offering or sale of the relevant
leases.


    3
     A DNA is not itself a NEPA document; it is not subject to public
comment or consultation with other federal agencies. S. Utah
Wilderness All. v. Norton, 457 F. Supp. 2d 1253, 1255 (D. Utah 2006).
                      NAEC V. USDOI                          9

II. The 2017 Lease Sale

    In August 2017, BLM issued a call for nominations and
comments on all unleased tracts for the 2017 lease sale.
Several of the Plaintiffs submitted a joint comment letter
arguing that BLM should not hold the proposed lease sale.
Their letter contended that BLM was required either to
prepare a new, “site-specific” NEPA analysis for the sale, or
to retain the authority to prohibit future activities on the
leased land.

    In September, BLM issued a DNA evaluating the NEPA
adequacy of the 2012 EIS respecting a proposal to offer
leases on all of the remaining tracts within the lands the IAP
made available for leasing, a total of about 10.3 million
acres. The DNA asserted that the current proposal was part
of the preferred alternative analyzed in the 2012 EIS, and
that no new information or circumstances substantially
changed the analysis.

    BLM opened the bidding process in December 2017.
Intervenor bid on seven of the 900 available tracts, covering
roughly 80,000 acres. BLM received no other bids on any
of the offered tracts. BLM accepted Intervenor’s bids in
January 2018. During this same period, the USGS published
an updated Assessment of Undiscovered Oil and Gas
Resources in formations underlying the Reserve, raising the
estimate of technically recoverable oil to 8.7 billion barrels.

   In early February, Plaintiffs filed a Complaint against
Federal Defendants alleging that BLM had conducted the
2017 lease sale without complying with NEPA. The
Complaint asserted two alleged causes of action: first, that
BLM failed to prepare a NEPA analysis, and second, that
BLM failed to take a “hard look” at environmental impacts.
See Baltimore Gas & Elec. Co. v. Nat. Res. Def. Council,
10                   NAEC V. USDOI

Inc., 462 U.S. 87, 97 (1983) (“Congress in enacting NEPA
. . . required only that the agency take a ‘hard look’ at the
environmental consequences before taking a major action.”
(quoting Kleppe v. Sierra Club, 427 U.S. 390, 410 n.21
(1976))). The Complaint highlighted the updated USGS
Assessment along with several other recent developments
that it claimed BLM had failed to properly analyze.

    Later that month, BLM issued a nine-page Revised DNA
that discussed several of those recent developments. The
Revised DNA found the updated USGS Assessment
unusable because it did not provide an estimate of
economically recoverable resources, and because it included
oil and gas underlying land and sea adjacent to the Reserve.
It also found several other developments insignificant
because the 2012 EIS had “already erred on the conservative
side and over analyzed likely potential impacts.” BLM’s
Acting Alaska State Director approved the Revised DNA
and executed the seven leases purchased by Intervenor on
the same day.

    In May, Plaintiffs filed a First Amended Complaint that
added a third cause of action, claiming that BLM had
violated its own NPRPA regulations by issuing the Revised
DNA “after it had already conducted the 2017 lease sale.”
See 43 C.F.R. § 3131.2(b).

III.   Proceedings in the District Court

    On cross-motions for summary judgment, the district
court ruled in favor of Defendants. The court concluded that
Plaintiffs were not asserting a time-barred claim that the
2012 EIS failed to take a hard look at environmental
consequences. Nevertheless, the court held that BLM was
not required to prepare a new NEPA document for the 2017
lease sale.
                          NAEC V. USDOI                                 11

    The court concluded that its decision was controlled by
Northern Alaska Environmental Center v. Kempthorne,
457 F.3d 969 (9th Cir. 2006). The court interpreted
Kempthorne to support Plaintiffs’ argument that BLM must
prepare a NEPA document before issuing leases wherein
BLM does not retain the authority to prohibit future on-the-
ground activities. However, the court read Kempthorne as
validating BLM’s position that the 2012 EIS was the
required document.          The court further interpreted
Kempthorne to hold that parcel-specific analysis was not
required until BLM was reviewing actual exploration and
development proposals. The court noted that Kempthorne
differed from this case due to the passage of time between
the EIS and the lease sale, but concluded that this distinction
was relevant only to whether supplementation might be
required, which Plaintiffs did not allege. 4

    Plaintiffs timely appealed.

   JURISDICTION AND STANDARD OF REVIEW

    We have jurisdiction pursuant to 28 U.S.C. § 1291. We
review de novo the district court’s grant of summary
judgment upholding an agency decision. Kempthorne,
457 F.3d at 975. Because NEPA does not contain its own
provision for judicial review, we review BLM’s compliance
with NEPA pursuant to the APA. Ka Makani ‘O Kohala
Ohana Inc. v. Water Supply, 295 F.3d 955, 959 (9th Cir.
2002). 5 Where an agency’s decision not to prepare an EIS
     4
       The court concluded in any event that “supplementation would
likely have been unnecessary.”
    5
       Defendants do not renew on appeal the argument they made to the
district court that the court lacked subject matter jurisdiction because the
original complaint was filed before final agency action had occurred for
12                        NAEC V. USDOI

turns on a threshold legal question regarding NEPA
applicability, rather than a predominantly factual or
technical decision, we review under a standard of
“reasonableness.” Id. at 959 & n.3 (citing Northcoast Envtl.
Ctr. v. Glickman, 136 F.3d 660, 667 (9th Cir. 1998); see also
High Sierra Hikers Ass’n v. Blackwell, 390 F.3d 630, 640
(9th Cir. 2004). 6

                STATUTE OF LIMITATIONS

    We begin by rejecting Defendants’ threshold argument
that Plaintiffs’ lawsuit is entirely time barred by the NPRPA.
To the extent Plaintiffs argue that the 2017 lease sale was a
distinct federal action requiring a tiered or stand-alone
NEPA analysis, we find their challenge is justiciable.




purposes of the APA. See 5 U.S.C. § 704. However, because
jurisdiction is something we must consider sua sponte, see Gonzalez v.
Thaler, 565 U.S. 134, 141 (2012), we nevertheless hold expressly that
the district court correctly relied on Northstar Financial Advisors Inc. v.
Schwab Investments, 779 F.3d 1036 (9th Cir. 2015), which allows us to
rely on an amended complaint that satisfies the jurisdictional defects of
an original complaint. See id. at 1043–48.
     6
      Where an agency’s decision not to prepare an EIS is based on
preparing a NEPA “environmental assessment” (EA) and concluding
therein that an action will have no significant impacts, we review under
the familiar “arbitrary and capricious” standard. Northcoast, 136 F.3d at
666–67 (citing Marsh v. Or. Nat. Res. Council, 490 U.S. 360, 376–77
(1989)). This same standard applies where an agency’s decision not to
supplement an EIS is based on its conclusion that new information or
circumstances do not rise to the level of significance, such as the
determinations BLM made in the DNA and Revised DNA. See id. As
discussed below, this case gives us no occasion to review either such
decision.
                       NAEC V. USDOI                           13

    The NPRPA contains the following statute of
limitations:

        Any action seeking judicial review of the
        adequacy of any program or site-specific
        environmental impact statement under
        section 102 of the National Environmental
        Policy Act of 1969 (42 U.S.C. 4332)
        concerning oil and gas leasing in the National
        Petroleum Reserve--Alaska shall be barred
        unless brought in the appropriate District
        Court within 60 days after notice of the
        availability of such statement is published in
        the Federal Register.

42 U.S.C. § 6506a(n)(1). Defendants argue that Plaintiffs
“necessarily” challenge the adequacy of the 2012 EIS,
regardless of how Plaintiffs attempt to characterize their
complaint, and that the NPRPA statute of limitations
therefore bars their claims. Cf. Turtle Island Restoration
Network v. U.S. Dep’t of Commerce, 438 F.3d 937, 944–45
(9th Cir. 2006) (in applying Magnuson Act statute of
limitations for challenging regulations promulgated
thereunder, “the decisive question is whether the regulations
are being attacked, not whether the complaint specifically
asserts a violation of the Magnuson Act”). Of Plaintiffs’
three claims, we find that it is possible to resolve the first and
third without an untimely adjudication of the adequacy of the
2012 EIS. We find that Plaintiff’s second claim, however,
is potentially barred by the statute of limitations, depending
on how we resolve the first claim.

  Plaintiffs’ first and third claims allege that BLM violated
NEPA and its own NPRPA regulations by failing to prepare
14                       NAEC V. USDOI

an environmental assessment (EA) 7 or EIS for the 2017 lease
sale. In order to adjudicate these claims, we must determine
whether the 2012 EIS was the EIS for the 2017 lease sale, as
BLM argues. Provided we are mindful that our inquiry not
amount to “judicial review of the adequacy of” the 2012 EIS,
the statute of limitations does not prevent us from resolving
this issue. If the 2012 EIS was the EIS for the 2017 lease
sale, then BLM did not fail to prepare an EIS, and Plaintiffs’
first and third claims fail on the merits. If the 2012 EIS was
not an EIS for the 2017 lease sale—in other words, if the
2017 lease sale required at least a tiered EA regardless of the
adequacy of the 2012 EIS—then Plaintiffs’ first and third
claims are not affected by the statute of limitations.

    Plaintiffs’ second claim is that BLM failed to take a hard
look at the impacts of the 2017 lease sale. If the 2012 EIS
was the EIS for the 2017 lease sale, then Defendants are
correct that Plaintiffs’ second claim “necessarily” must
challenge the adequacy of the 2012 EIS, and is barred by the
statute of limitations. 8 If the 2012 EIS was not an EIS for
the 2017 lease sale, then Plaintiffs’ second claim implicates



     7
       If an agency is unsure whether a project may have significant
environmental impacts and thus require an EIS, the agency can take the
intermediate step of preparing an EA, which requires less detail and less
formality of procedure than an EIS, and does not require the analysis of
alternatives. 40 C.F.R. §§ 1501.4(b), 1508.9. The purpose of the EA is
to determine whether the proposal may have significant impacts: If so,
the agency must go on to prepare an EIS. See id. §§ 1501.4(c), 1502.14,
1508.9(a)(1). If not, the agency certifies its conclusion with a Finding
of No Significant Impact (FONSI). Id. § 1508.13.
     8
       To the extent Plaintiffs claim that BLM failed to take a hard look
at information that became available after the 2012 EIS, the appropriate
rubric would be supplementation, which Plaintiffs have waived.
                         NAEC V. USDOI                              15

only the DNA or Revised DNA, 9 and is not barred by the
statute of limitations.

                            ANALYSIS

    In light of the above, our task is to resolve not only
whether the 2012 EIS was the EIS for the 2017 lease sale,
but also how that determination should be made.

    Plaintiffs are correct that under a proper reading of our
case law, the 2017 lease sale represented an irretrievable
commitment of resources necessitating site-specific analysis
in an EIS. However, we disagree with Plaintiffs’ suggestion
that a programmatic EIS prepared for a broad-scale land use
plan categorically cannot provide the site-specific analysis
required for irretrievable commitments of resources. Thus,
we reject the claim that the 2012 EIS was categorically a
different type of EIS than what was required for the 2017
lease sale. Furthermore, Plaintiffs fail to convince us that
the required degree of site specificity was so clearly greater
than that provided in the 2012 EIS that we cannot reasonably
construe the 2012 EIS as covering future lease sales.

    Drawing from our precedents regarding the importance
of accurately describing the action being taken, and from the
NEPA regulations requiring agencies to properly define the
scope of proposals which are the subject of an EIS, we
conclude that the proper inquiry is whether the initial EIS
defined its scope as including the subsequent action. To the
extent the defined scope is ambiguous on this question, we
find it appropriate to consider whether the defined scope of

    9
      We assume that without a properly tiered NEPA document
incorporating analysis in the 2012 EIS by reference, BLM could not rely
on any such analysis in defending a hard look challenge.
16                    NAEC V. USDOI

the initial EIS can be reasonably construed to include the
subsequent action given the analysis performed therein, in
light of applicable laws and regulations.

    Applying this framework to the facts in this case, we
conclude that we can reasonably construe the defined scope
of the 2012 EIS to include the 2017 lease sale. Thus, we
defer to BLM’s position that the 2012 EIS was the EIS for
the 2017 lease sale.

I. Site-Specific Analysis

    We agree with Plaintiffs that the 2017 lease sale required
some form of site-specific analysis. “The critical inquiry in
considering the adequacy of an EIS prepared for a large
scale, multi-step project is not whether the project’s site-
specific impact should be evaluated in detail, but when such
detailed evaluation should occur.” California v. Block,
690 F.2d 753, 761 (9th Cir. 1982) (emphasis added). “This
threshold is reached when, as a practical matter, the agency
proposes to make an ‘irreversible and irretrievable
commitment of the availability of resources’ to a project at a
particular site.” Id. (quoting Sierra Club v. Hathaway,
579 F.2d 1162, 1168 (9th Cir. 1978)).

    Whether a lease is a critical decision requiring an EIS
depends on whether the lease reserves the agency’s absolute
right to preclude surface-disturbing activity. See Pit River
Tribe v. U.S. Forest Serv., 469 F.3d 768, 782 (9th Cir. 2006).
A lease that reserves an absolute right to prohibit surface-
disturbing activities, sometimes called a “no surface
occupancy” (NSO) lease, does not irreversibly and
irretrievably commit any resources and therefore does not
require a site-specific EIS. Id. (citing Friends of Southeast’s
Future v. Morrison, 153 F.3d 1059, 1063–64 (9th Cir.
1998)). A lease that does not retain an absolute right to
                        NAEC V. USDOI                              17

prohibit surface-disturbing activities, even if it retains the
right to impose mitigating conditions, constitutes an
irreversible and irretrievable commitment of resources and
therefore does require a site-specific EIS. Id. (citing Bob
Marshall All. v. Hodel, 852 F.2d 1223, 1226–27 (9th Cir.
1988); Conner v. Burford, 848 F.2d 1441, 1449–51 (9th Cir.
1988)).

     For instance, in Conner, the Forest Service prepared EAs
for the sale of oil and gas leases in the Flathead and Gallatin
National Forests in Montana. 848 F.2d at 1443. The EAs
concluded that the mere sale of the leases would have no
significant impact on the environment, largely because any
proposed surface-disturbing activities would be subject to
future NEPA analysis. Id. at 1443, 1446. We agreed with
the Forest Service with respect to the leases containing an
NSO provision, but disagreed with regard to non-NSO
leases. Id. at 1448, 1451. We explained that NSO leases
really provide the leaseholder only a “right of first refusal,”
that is, a priority with respect to other developers. Id. at
1448. Thus, an NSO lease “does not constitute an
irretrievable commitment of resources.” Id. The opposite
was true of the non-NSO leases. Id. at 1451 (agreeing with
Sierra Club v. Peterson, 717 F.2d 1409, 1412–15 (D.C. Cir.
1983)).       We explained that the non-NSO leases
“relinquish[ed] the ‘no action’ alternative,” consideration of
which, among other “reasonable alternatives to the proposed
action,” is the “heart” of the EIS. Id. NEPA did not allow
the Forest Service to delay preparation of an EIS until a point
at which the “no action” option was no longer available.
Id. 10


    10
      The Forest Service in Conner also argued that the non-NSO leases
could not have a significant impact on the environment because they
18                       NAEC V. USDOI

    “There is no question” that NPRPA oil and gas leases
constitute “an irretrievable commitment of resources,” and
thus require “site specific analysis in [an] EIS.”
Kempthorne, 457 F.3d at 975–76. However, the dispute here
is not whether an EIS must be prepared for the leases, but
whether an EIS has already been prepared for the leases.

     A. Programmatic EISs

    Plaintiffs appear to claim that a single document cannot
be both a programmatic EIS for a broad-scale land
management plan and also a site-specific EIS for an
irretrievable commitment of resources. See Native Village
of Point Hope v. Jewell, 740 F.3d 489, 497 (9th Cir. 2014)
(distinguishing between the EIS analysis required for a
programmatic plan that guides management of multiple-use
resources, versus for a site-specific plan at the
implementation stage). Plaintiffs are incorrect.

    In Block, we rejected a similar argument by the Forest
Service that a programmatic EIS categorically “need not
contain the type of detailed site-specific information
normally contained in an EIS prepared for a more narrowly
focused project.” 690 F.2d at 761. Instead, we looked to the
actual federal action being taken, which we concluded
consisted of both a broad-scale management plan and a
series of site-specific critical decisions that required site-
specific analysis. See id. at 762–63. Though recognizing
that a detailed site-specific analysis for a plan covering a
very large area—in that case, a nationwide plan—would be

subjected future surface-disturbing activities to reasonable mitigation
requirements. 848 F.2d at 1450. We noted that an EIS was required if
there was even a chance that the mitigation measures would fail to reduce
impacts to insignificance, which we thought highly likely given the
typical scale of oil and gas activities. Id.
                      NAEC V. USDOI                          19

difficult and involve significant uncertainty, we noted that
“[t]he scope of the undertaking here, however, was the
Forest Service’s choice and not the courts’.” Id. at 765.
Block demonstrates that a single “federal action” for
purposes of NEPA can be both broad-scale and site-specific,
and can be evaluated at both of those levels in a single EIS.

    Friends of Yosemite Valley v. Norton is not to the
contrary. 348 F.3d 789 (9th Cir. 2003), clarified by 366 F.3d
731 (9th Cir. 2004).         There, we concluded that a
programmatic EIS prepared for the Merced River
management plan did not need to include detailed site-
specific analysis. Id. at 800–01. However, our conclusion
regarding the required level of site specificity was tailored to
our conclusion regarding the nature of the federal action that
was the subject of the EIS. See id. Having concluded that
the management plan provided only broad guidelines and
made no irreversible and irretrievable commitment of
resources, we held that the EIS “contain[ed] sufficiently
specific data and information for [its] purpose.” Id. at 801.
Friends of Yosemite Valley does not dictate that any EIS
labeled “programmatic” or covering a broad-scale
management plan cannot also cover site-specific actions and
the impacts thereof where appropriate.

    In Kempthorne, BLM had prepared a combined IAP and
EIS to open parts of the Reserve within the Northwest
Planning Area to oil and gas leasing. 457 F.3d at 973–74;
see NAEC v. Norton, 361 F. Supp. 2d 1069, 1072 (D. Alaska
2005). The EIS conducted its analysis on a scale similar to
that of the 2012 EIS here, using “hypothetical future
projections of what might be undertaken in the exploration
and development phases” to analyze impacts “on a resource
by resource basis,” while “not attempt[ing] to examine the
impact on specific parcels.” 457 F.3d at 974. In evaluating
20                        NAEC V. USDOI

the adequacy of that EIS, we treated it as equally covering
“the leases” and “the leasing program.” Id. at 976. Plaintiffs
had challenged the EIS specifically on the assumption that it
covered both “planning decisions and site specific . . .
resource commitments,” i.e., both the IAP and the individual
leases. 361 F. Supp. 2d at 1078. Plaintiffs argued that the
EIS was inadequate because, while it did provide the
programmatic analysis necessary for planning decisions, it
did not provide the site-specific analysis required for
resource commitments. 11 Id. Although we did not consider
the question directly, Kempthorne provides strong support
for the conclusion that nothing legally precludes BLM from
analyzing both an IAP and NPRPA lease sales in the same
EIS.

    In sum, nothing in NEPA or our caselaw prevents
agencies from using a single document to undertake both a
programmatic-level analysis and a site-specific analysis at
the level appropriate for any irretrievable commitments of
resources. Thus, the fact that the 2012 EIS provided a
programmatic-level analysis for the IAP does not preclude
the legal possibility that it also served as the necessary site-
specific analysis for future lease sales.

     B. Degree of Site Specificity

    Theoretically, one could argue that the 2012 EIS could
not have been the NEPA analysis for the 2017 lease sale if
NEPA clearly required a significantly greater degree of site
specificity for the analysis of NPRPA lease sales than was


     11
       Here, Plaintiffs take a different approach by arguing that the 2012
EIS simply “was” a programmatic EIS for the IAP, and “was not” a site-
specific EIS for a lease sale.
                      NAEC V. USDOI                         21

provided in the 2012 EIS. However, we are not persuaded
that NEPA so required.

    The question of whether any site-specific analysis is
required, addressed above, is different from the question of
what “degree of site specificity” is required. Kempthorne,
457 F.3d at 976. “The detail that NEPA requires in an EIS
depends upon the nature and scope of the proposed action.”
Block, 690 F.2d at 761. “If it is reasonably possible to
analyze the environmental consequences” of a particular
type at a particular stage, “the agency is required to perform
that analysis.” Kern, 284 F.3d at 1072 (requiring analysis of
foreseeable impacts to particular species at the resource
management plan stage, notwithstanding that those impacts
could be analyzed more precisely at a later site-specific
project stage). “We will defer to the agency’s judgment
about the appropriate level of analysis so long as the EIS
provides as much environmental analysis as is reasonably
possible under the circumstances, thereby ‘provid[ing]
sufficient detail to foster informed decision-making’ at the
stage in question.” Native Village of Point Hope, 740 F.3d
at 498 (quoting Friends of Yosemite Valley, 348 F.3d at 800).

    Thus, when an oil and gas lease constitutes an
“irretrievable commitment of resources,” the required
degree of analytical site specificity depends on the
specificity of the “reasonably foreseeable” environmental
impacts in light of the factual context. New Mexico ex rel.
Richardson v. BLM, 565 F.3d 683, 718 (10th Cir. 2009). For
instance, in Richardson, the challenged lease pertained to a
relatively small parcel (less than 2,000 acres);
“[c]onsiderable exploration ha[d] already occurred on
parcels adjacent to the [leased parcel]”; “a natural gas supply
[was] known to exist beneath these parcels”; and the record
contained sufficient information on which to predict the
22                       NAEC V. USDOI

number of wells that the leaseholder would want to
construct. Id. at 717–18. Given these facts, the Tenth
Circuit concluded that “the impacts of this planned gas field
were reasonably foreseeable before the . . . lease was
issued.” Id. at 718.

   By contrast, in Kempthorne, we held that the plaintiffs’
“particular challenge to site specificity lack[ed] merit”
because “parcel by parcel” effects were “currently
unidentifiable” given the facts at hand. 12 457 F.3d at 977.
Though acknowledging that some degree of site-specific
analysis was required, 13 we upheld BLM’s method of using

     12
       We reasoned in part that “NEPA could never be satisfied” if BLM
had to conduct “an analysis of the environmental effect with respect to
each parcel involved in a possible lease for exploration and
development,” because “until the lessees do exploratory work, the
government cannot know what sites will be deemed most suitable for
exploratory drilling, much less for development.” 457 F.3d at 976.
However, we did not address Conner’s admonition that the agency could
avoid this difficulty by issuing non-NSO leases. See 848 F.2d at 1451.
Nevertheless, Kempthorne is not inconsistent with Conner. We
understand the “hypothetical situations” analysis in the Kempthorne EIS,
457 F.3d at 976, to have satisfied Conner’s requirement to “estimate
what [the] effects might be,” 848 F.2d at 1450.
     13
         Native Village of Point Hope does not contradict this
interpretation of Kempthorne. See Native Village of Point Hope,
740 F.3d at 493–94 (“An agency is not required at the lease sale stage
to analyze potential environmental effects on a site-specific level of
detail.” (citing Kempthorne, 457 F.3d at 975–76)). Native Village of
Point Hope involved the Outer Continental Shelf Lands Act (OSCLA),
43 U.S.C. §§ 1331–1356. Id. Under OSCLA, a lease conveys “no right
to proceed with full exploration, development, or production . . . [but
rather] only a priority in submitting plans to conduct these activities.”
Tribal Village of Akutan v. Hodel, 869 F.2d 1185, 1187–88 (9th Cir.
1988) (quoting Sec’y of the Interior v. California, 464 U.S. 312, 339
(1984)). Thus, OSCLA leases are necessarily NSO leases, and unlike
those at issue in this case. Accordingly, we had no occasion in Native
                         NAEC V. USDOI                              23

“hypothetical situations that represented the spectrum of
foreseeable results” as a way of analyzing oil and gas leasing
in the Reserve’s Northwest Planning Area. 457 F.3d at 976.

     We find the facts in this case bear a far greater
resemblance to those in Kempthorne than those in
Richardson. Accordingly, Kempthorne dictates that the type
of analysis employed in the 2012 EIS may qualify as the site-
specific analysis required of a critical decision given
appropriate factual circumstances. As Plaintiffs urge,
Kempthorne does not preclude the theoretical possibility that
some greater degree of site specificity (even if not parcel-by-
parcel) was “reasonably possible,” Kern, 284 F.3d at 1072,
or that more site-specific impacts were “reasonably
foreseeable,” Richardson, 565 F.3d at 718, than that
conducted or those analyzed in the 2012 EIS. However,
because we ultimately conclude that the 2012 EIS covered
future lease sales, the NPRPA statute of limitations makes it
unnecessary for us to resolve whether BLM employed the
precise degree of site specificity required. While we agree
with Plaintiffs that some degree of site-specific EIS analysis
is required for NPRPA leases, we are not persuaded that the
degree required for the 2017 lease sale was so clearly greater
than that reflected in the 2012 EIS that the 2012 EIS could
not have covered the 2017 lease sale.



Village of Point Hope to consider the nuance Plaintiffs assert regarding
the difference between site-specific analysis, which Kempthorne
acknowledged was required to some degree, and parcel-by-parcel
analysis, which Kempthorne rejected as impossible at the NPRPA
leasing stage. In any event, NPRPA leases were not before us in Native
Village of Point Hope, so we could not have decided their requirements.
Because OSCLA leases appear to be NSO leases by statute, our
statement was accurate for the purposes at hand.
24                   NAEC V. USDOI

II. Subsequent Actions

    We next consider other potential methods for
determining NEPA’s requirements for an action that is
separated from an EIS by the passage of time.

    As background, NEPA regulations provide two
frameworks within which additional NEPA analysis may
occur after an initial EIS is finalized: namely, tiering and
supplementation. Tiering refers to the incorporation by
reference in subsequent EISs or EAs, which concentrate on
issues specific to the current proposal, of previous broader
EISs that cover matters more general in nature. 40 C.F.R.
§ 1508.28. Supplementation refers to the process of
updating a previous EIS in situations where the agency
makes substantial changes to the proposed action, or there
are significant new circumstances or information. Id.
§ 1502.9(c). The NEPA regulations do not provide any
express guidance for determining whether to prepare a tiered
NEPA analysis or a supplemental NEPA analysis in
borderline cases. See Daniel R. Mandelker et al., NEPA Law
& Litig. § 9:12 (2d ed., Aug. 2019 update).

     A. NEPA Adequacy

    To support their respective contentions about what type
of NEPA analysis was required for the 2017 lease sale,
Plaintiffs and Defendants rely in part on cases which imply
that the relevant inquiry is whether the previous EIS
adequately analyzed the impacts of the subsequent action.
We decline to take this approach.

   In Blue Mountains Biodiversity Project v. Blackwood,
we concluded that the Forest Service’s previous
programmatic forest plan EIS did not obviate the need for an
EIS for several proposed timber salvage sales in an area
                         NAEC V. USDOI                               25

burned by a large wildfire. 161 F.3d 1208, 1210, 1214 (9th
Cir. 1998). The Forest Service argued that its EA for one of
the salvage sales was sufficient given that it tiered to the
forest plan EIS for additional analysis. Id. at 1214. We
disagreed, finding that the forest plan EIS analysis was
inadequate because it “d[id] not, and could not, evaluate the
impacts of this catastrophic fire, or the additional
environmental impacts that large scale logging of severely
burned areas could bring.” Id. Plaintiffs here also allege
significant developments that could not have been evaluated
in the 2012 EIS because they did not take place until later.
Our decision in Blue Mountains is of little utility to us in
evaluating this case, however, because the fact that the
proposed timber salvage sales constituted a new project was
not in dispute. 14 Instead, the dispute focused on whether the
EA for the new project contained sufficient analysis. Here,
BLM did not prepare a contemporary NEPA analysis (such
as an EA) for the 2017 lease sale. Rather, BLM argues that
the 2012 EIS did contemplate the 2017 lease sale and already
performed the necessary analysis.

    In Pit River Tribe, the plaintiffs challenged a 1998
geothermal lease extension in the volcanic Medicine Lake
Highlands in California. The agencies involved had
prepared a nationwide programmatic EIS in 1973, which
“d[id] not adequately address the potential impacts of
leasing.” 469 F.3d at 783. Subsequently, the agencies
prepared EAs in 1981 and 1984 which considered leases but
did not consider the impacts of “actual geothermal
development.” Id. at 784. The agencies then issued leases
in 1988 which did not reserve an absolute right to prohibit

    14
        Furthermore, the timber salvage sales involved surface-disturbing
activities, making them more analogous to oil and gas permits for
exploration or development than to oil and gas leases. Id. at 1210.
26                   NAEC V. USDOI

development. Id. Because the statute of limitations had run,
the plaintiffs challenged only the 1998 extensions of those
leases, and not the original 1988 leases. Id. at 781. The
agencies argued that they had completed the required NEPA
analysis in 1973, 1981, and 1984. Id. We disagreed, and
concluded that the agencies were required to prepare a new
EIS for the 1998 lease extensions. Id. at 784.

    Pit River Tribe illustrates that the adequacy of analysis
in previous NEPA documents for the present action may
influence whether we construe those NEPA documents as
covering the present action. Relatedly, Pit River Tribe
shows that adequacy may remain relevant even after the
statute of limitations has run. However, it appears that the
agencies in Pit River Tribe conceded that the lease
extensions constituted a new action, arguing rather that a
new NEPA analysis was unnecessary because the leases only
maintained the status quo. See id. We held that the
extensions did not simply maintain the status quo because
they granted a new right to additional years of development
which had not been granted previously. Id.

     In Mayo v. Reynolds, the D.C. Circuit considered a
NEPA claim where the plaintiff alleged that the National
Park Service “was required to issue a new EA or EIS” for
each year’s proposed elk hunting authorization pursuant to a
fifteen-year elk-reduction program in Grand Teton National
Park. 875 F.3d 11, 14, 19 (D.C. Cir. 2017). The Park
Service argued that it had prepared the required analysis in
an initial EIS for the entire fifteen-year program, and the
court agreed. Id. at 14–15. The court endorsed the Park
Service’s assertion that although NEPA requires agencies to
take a “hard look” at environmental impacts, NEPA “does
not . . . require the agency to take a new look every time it
takes a step that implements a previously-studied action, so
                      NAEC V. USDOI                         27

long as the impacts of that step were contemplated and
analyzed by the earlier analysis.” Id. The court concluded
that the original EIS had already taken a hard look at all the
potential impacts associated with each year’s hunt. Id. at 21.

    Our concern with relying on NEPA adequacy as the sole
determinant of whether an action requires a “new look,” as
Mayo puts it, is that this robs the statute of limitations of
effect in certain situations. Specifically, the statute of
limitations becomes meaningless where some steps of a
previously studied action remain to occur after expiration of
the limitations period. Such a result might discourage
agencies from bothering to prepare EISs that contemplate the
entirety of a multi-step, long-term project at all, contrary to
NEPA’s goals that agencies analyze connected and
cumulative actions as much as possible in one EIS. See
40 C.F.R. § 1508.25(a). Nor are we satisfied with saying
that, if the relevant inquiry is whether the initial EIS was
adequate, the statute of limitations simply bars the inquiry.

   B. Underlying Plan or Program

     Another approach is to look not at the initial NEPA
analysis, but at the underlying plan or program. For
instance, in Mayo, the D.C. Circuit relied in part on its
conclusion that the plaintiff had not shown that the hunting
authorizations deviated in any significant way from the
fifteen-year program. 875 F.3d at 21. While we agree that
conformity with the initially analyzed plan or program is
relevant to NEPA requirements, we do not think it sufficient
to answer our question here. After all, the tiering regulations
generally assume that the subsequent site-specific action is
consistent with the previously studied broad-scale plan.
“Nothing in the tiering regulations suggests that the
existence of a programmatic EIS for a [regionwide
management] plan obviates the need for any future project-
28                   NAEC V. USDOI

specific EIS, without regard to the nature or magnitude of a
project.” Blue Mountains, 161 F.3d at 1214. Moreover, a
focus on plan compliance fails to account for whether
members of the public have fair notice of when they should
challenge the NEPA compliance of a particular action.

     We also reject Plaintiffs’ argument that Norton v.
Southern Utah Wilderness Alliance (SUWA) dictates that
any action occurring after the adoption of a land use
management plan is necessarily a new action subject to the
tiering rubric. 542 U.S. 55 (2004). In SUWA, the plaintiffs
argued that BLM was required to supplement its previous
NEPA analysis for land use plans governing off-road vehicle
use on public lands in Southern Utah because there was new
evidence available that such use had substantially increased.
See id. at 61. The Supreme Court held that supplemental
NEPA analysis can be required only where “there remains
‘major Federal actio[n]’ to occur.” Id. at 73 (quoting Marsh
v. Or. Nat. Res. Council, 490 U.S. 360, 374 (1989)). In the
circumstances of that case, the Court explained that the
original EIS supported BLM’s adoption of a land use plan,
and that “that action [was] completed when the plan [was]
approved.” Id. There was thus “no ongoing ‘major Federal
action’ that could require supplementation (though BLM is
required to perform additional NEPA analyses if a plan is
amended or revised).” Id. (citations omitted).

    Plaintiffs argue that SUWA dictates that the 2012 EIS
covered only the adoption of the IAP, and that
supplementation is not the appropriate framework for
evaluating this case because Plaintiffs do not ask for an
amendment to the IAP. But the circumstances here are
different than in SUWA. In SUWA, BLM did not claim to be
engaged in an ongoing action supported by the original
NEPA analysis; what the plaintiffs challenged was BLM’s
                     NAEC V. USDOI                         29

inaction. See id. at 61, 72–73. NEPA supplementation
regulations did not require BLM to initiate a proposal for
new action, such as amending the plans. See id. at 73. Here,
BLM does argue that it is engaged in an ongoing action
supported by the 2012 EIS, to which the NEPA
supplementation regulations apply. Nothing in SUWA
precludes BLM from structuring its activities in this way.

   C. Defined Scope

    In light of our concerns regarding the statute of
limitations and the need for fair notice, we look instead to
whether the initial EIS purported to be the EIS for the
subsequent action.

    Our precedents support looking to the language of the
EIS to help us form “an accurate description of the
[agency’s] proposed action.” Friends of Yosemite Valley,
348 F.3d at 801; see also Block, 690 F.2d at 761 (“The
starting point in our analysis is ‘to describe accurately the
“federal action” being taken.’” (quoting Aberdeen &
Rockfish R.R. Co. v. Students Challenging Regulatory
Agency Procedures (S.C.R.A.P.), 422 U.S. 289, 322
(1975))). For instance, in NAEC v. Lujan, plaintiffs
challenged the adequacy of the National Park Service’s EISs
regarding mining in three national parks in Alaska, arguing
that the EISs contained insufficiently site-specific analysis
given the agency’s decision to authorize mining operations.
See 961 F.2d 886, 887, 890 (9th Cir. 1992). We rejected
plaintiffs’ characterization of the federal action, relying on
the EISs’ own description that “[i]f, however, the National
Park Service determines that the impacts of proposed mining
operations would violate the decision standards for plan of
operations approval, and the effects could not be sufficiently
mitigated, the plan would be disapproved.” Id. at 890
30                    NAEC V. USDOI

(citation omitted). We thus concluded that no irreversible
and irretrievable commitment of resources had occurred. Id.

    Similarly, the D.C. Circuit in Mayo relied on the EIS’s
statement that its “level of analysis [was] sufficient to allow
several management actions to be carried out without having
to complete additional environmental analyses (e.g.,
environmental assessments) prior to implementation.”
875 F.3d at 18. The court factored this EIS statement into
its ultimate determination that the Park Service was not
required to prepare “additional environmental analyses (e.g.,
environmental assessments)” prior to each year’s elk hunt.
See id.

    Furthermore, the NEPA regulations emphasize the need
for EISs to carefully define the proposal(s) under
consideration, and specify detailed criteria to be consulted in
the process. For example, the regulations provide that:

       Agencies shall make sure the proposal which
       is the subject of an environmental impact
       statement is properly defined. Agencies shall
       use the criteria for scope (§1508.25) to
       determine which proposal(s) shall be the
       subject of a particular statement. Proposals
       or parts of proposals which are related to each
       other closely enough to be, in effect, a single
       course of action shall be evaluated in a single
       impact statement.

40 C.F.R. § 1502.4(a). The regulations further specify that
the following types of actions “should” be included within
the scope of a single EIS:

       (1) “Connected actions,” meaning actions
           that:
                        NAEC V. USDOI                             31

            (i)      “Automatically        trigger    other
                     actions,”

            (ii)     “Cannot or will not proceed”
                     without other actions, or

            (iii)    “Are interdependent parts of a
                     larger action and depend on the
                     larger      action  for    their
                     justification”; and

        (2) “Cumulative actions,” meaning actions
            that have cumulatively significant
            impacts.

Id. § 1508.25(a). A third category, “Similar actions,” “may”
be included within the scope of a single EIS. Id. Agencies
must use a public “scoping” process to decide the scope of
“actions, alternatives, and impacts to be considered in an
environmental impact statement.” Id. §§ 1501.7, 1508.25.

     Thus, in deciding whether a previous EIS is the EIS for
a subsequent action, we find it appropriate to rely on an
EIS’s defined scope. If the defined scope of the initial EIS
included the subsequent action, NEPA requirements for the
subsequent action would fall under the supplementation
rubric. If the defined scope of the initial EIS did not include
the subsequent action (but presumably the analysis in the
initial EIS is to some extent relevant), NEPA requirements
for the subsequent action would fall under the tiering
rubric. 15 Of course, we recognize that the defined scope of
    15
       These two frameworks are not mutually exclusive. If an agency
wishes to tier a new NEPA analysis to a previous NEPA analysis, the
agency may have to take into account whether the previous NEPA
analysis requires supplementation. Also, we are not aware of anything
32                        NAEC V. USDOI

the initial EIS may be ambiguous with regard to whether it
does or does not include the precise subsequent action at
issue. Applying our standard of review, we must determine
whether the agency’s interpretation of the scope is
reasonable. Ka Makani, 295 F.3d at 959 & n.3.

    Although the adequacy of the initial EIS for purposes of
the subsequent action may be relevant in an extreme case,
where the inadequacy of analysis is so clear as to
demonstrate that the scope of the initial EIS cannot
reasonably be construed as including the subsequent action,
we do not think our scope inquiry constitutes “judicial
review of the adequacy” of the initial EIS within the meaning
of the NPRPA statute of limitations.               42 U.S.C.
§ 6506a(n)(1). It cannot reach the adequacy of the initial EIS
for those actions actually within its scope.

III.     Application

    We next undertake to determine how the 2012 EIS
defined its own scope. The 2012 EIS abstract identifies the
“Proposed Action” as the “National Petroleum Reserve-
Alaska Integrated Activity Plan/Environmental Impact
Statement,” which it states “is designed to determine the
appropriate management of all BLM-managed lands in the
[Reserve].” Under the heading, “What is BLM proposing to
do in this plan?” the Executive Summary similarly states that
BLM completed the combined IAP and EIS “to determine
the appropriate management of the BLM-administered lands
(public lands) in the nearly 23-million-acre Petroleum
Reserve.” It further highlights that “[a]mong the most


that would prevent an agency from performing the analysis required by
the tiering regulations in a document styled as a supplement to a previous
NEPA analysis.
                         NAEC V. USDOI                              33

important decisions the BLM will make through this plan is
what lands should be made available for oil and gas leasing
and with what protections for surface resources and uses.”
The section of the Introduction entitled “Scoping and Issues”
does not clearly articulate the “range of actions . . . to be
considered.” 40 C.F.R. § 1508.25. As relevant here, it says
only that “[t]he plan will examine a range of alternatives for
oil and gas leasing and development.” We find all these
high-level summaries are ambiguous as to whether the
“proposal which is the subject of” the EIS is merely to
designate certain lands as available for leasing, with actual
lease sale decisions to be proposed and analyzed at a later
point, or if the subject proposals include the actual offerings
and sales of the leases. 16 40 C.F.R. § 1502.4(a).

     However, a section of the Introduction regarding
“Requirements for Further Analysis” provides somewhat
greater guidance. This section states that “BLM anticipates
that this IAP/EIS will fulfill the NEPA requirements for the
first oil and gas lease sale.” As to future lease sales, it states
that “[p]rior to conducting each additional sale, the agency
would conduct a determination of the existing NEPA
documentation’s adequacy. If the BLM finds its existing
analysis to be adequate for a second or subsequent sale, the
NEPA analysis for such sales may require only an
administrative determination of NEPA adequacy.” It then
contrasts future “actions,” such as a “proposed exploratory

    16
        Similarly, Chapter 2 of the 2012 EIS, which describes the
Alternatives under consideration, explains that under “[a]ll of the
alternatives,” “BLM has discretion to offer for lease in any given lease
sale all or only some of the unleased lands that, based on the existing
IAP decision document, are available for leasing.” This language too is
ambiguous as to whether those discretionary lease sale offerings are an
aspect of the alternative proposals under consideration, or whether they
are distinct future actions subject to independent NEPA requirements.
34                    NAEC V. USDOI

drilling plan,” which “would require further NEPA analysis”
based on the specifics of the proposal.

    By stating that future lease sales might require only an
“administrative determination of NEPA adequacy,” as
opposed to “further NEPA analysis,” this section implies
that future leases are within the scope of the 2012 EIS. A
DNA could suffice only if the relevant question was whether
the lease sale required a supplemental EIS. See Idaho
Sporting Congress Inc. v. Alexander, 222 F.3d 562, 566 (9th
Cir. 2000) (recognizing a “limited role” for non-NEPA
evaluation procedures “for the purpose of determining
whether new information or changed circumstances require
the preparation of a supplemental EA or EIS”). If the
relevant question was whether the lease sale required its own
EIS, we assume BLM would have to prepare at least a tiered
EA to make this determination. Likewise, the fact that this
section does not describe future lease sales as future
“actions” implies that future lease sales are components of
the action that is the subject of the 2012 EIS. Finally, the
fact that this section claims that the 2012 EIS will entirely
fulfill the NEPA requirements for the first lease sale suggests
that all lease sales are within the scope of the subject action,
with the only potential trigger for additional NEPA analysis
being new information or circumstances arising before
subsequent sales—i.e., factors potentially requiring
supplementation. See 40 C.F.R. § 1502.9(c).

    As Plaintiffs point out, the 2012 EIS does not analyze the
impacts of any proposal for when to offer which particular
tracts of land for leasing, let alone alternative proposals that
vary by location, amount, or timing. However, we think this
is a criticism better directed at whether BLM considered
adequate alternatives in 2012 EIS, than at whether BLM
considered future lease sales at all. We see nothing in NEPA
                     NAEC V. USDOI                         35

that would in principle prevent BLM from analyzing a
proposed authorization of multiple, entirely discretionary
lease sales. Cf. Mayo, 875 F.3d at 20–22 (rejecting
plaintiffs’ argument that EIS for fifteen-year plan could not
satisfy EIS requirement for each year’s elk hunt because it
did not analyze the “timing, location, restrictions, and . . .
potential alternatives” for each hunt). Had Plaintiffs brought
a timely challenge against the 2012 EIS, they could have
argued that NEPA required consideration of a reasonable
alternative authorization of multiple lease sales that
employed particular criteria regarding how many and which
tracts to offer when. See Kempthorne, 457 F.3d at 978.
Furthermore, to the extent the minimal degree of site
specificity in the 2012 EIS might suggest that lease sales
were not within its scope, we have already rejected that
argument. Even if Kempthorne does not foreclose the
possibility that proper analysis of non-NSO NPRPA leases
requires some greater degree of site specificity than that
provided in the 2012 EIS, we are not persuaded that the
difference (if any) is so great as to make it unreasonable to
construe the scope of the 2012 EIS to include such leases.

    Although the expressly defined scope of the 2012 EIS is
somewhat ambiguous as to the question before us, we find
that the language regarding future NEPA requirements
provides reasonable notice that the intended scope
encompassed the actual lease sales. Furthermore, we do not
find it unreasonable to construe the scope of the 2012 EIS as
such when considering the analysis performed therein and
the law applicable to non-NSO NPRPA leases. Thus, we
defer to BLM’s reasonable position that the 2012 EIS was
the EIS for the 2017 lease sale. See Ka Makani, 295 F.3d
at 959 & n.3.
36                    NAEC V. USDOI

    Accordingly, Plaintiffs’ first and third claims fail on the
merits. BLM did not violate NEPA or its own NPRPA
regulations by failing to prepare a NEPA analysis for the
2017 lease sale before the 2017 lease sale took place,
because BLM prepared the required NEPA analysis in 2012.
The 2017 lease sale offering did not require a new tiered or
stand-alone NEPA analysis.

    Furthermore, because we conclude that the 2012 EIS was
the EIS for the 2017 lease sale, Plaintiffs’ second claim,
alleging that BLM failed to take a hard look at the impacts
of the 2017 lease sale, is time barred in part and waived in
the remainder. The NPRPA statute of limitations prevents
us from inquiring whether the 2012 EIS took a sufficiently
hard look at the impacts of the 2017 lease sale. Following
the 2012 EIS, BLM’s only remaining hard look obligation
with respect to the 2017 lease sale was to analyze new
circumstances and new information under the
supplementation rubric. See 40 C.F.R. § 1502.9(c). Because
Plaintiffs have disavowed a supplementation claim, we
consider this issue waived.

                      CONCLUSION

   For the foregoing reasons, we affirm the district court’s
grant of summary judgment in favor of Defendants.

     AFFIRMED.
