                  FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

SOUTH FORK BAND COUNCIL OF             
WESTERN SHOSHONE OF NEVADA;
TE- MOAK TRIBE OF WESTERN
SHOSHONE INDIANS OF NEVADA;
TIMBISHA SHOSHONE TRIBE;
WESTERN SHOSHONE DEFENSE
PROJECT; GREAT BASIN RESOURCE
WATCH,
              Plaintiffs-Appellants,        No. 09-15230
                v.                            D.C. No.
UNITED STATES DEPARTMENT OF THE           3:08-cv-00616-
                                             LRH-RAM
INTERIOR; UNITED STATES
BUREAU OF LAND MANAGEMENT;                    OPINION
GERALD M. SMITH, District
Manager, Battle Mountain Field
Office,
             Defendants-Appellees,
               and
BARRICK CORTEZ, INC.,
    Defendant-intervenor-Appellee.
                                       
        Appeal from the United States District Court
                 for the District of Nevada
         Larry R. Hicks, District Judge, Presiding

                  Argued and Submitted
         June 10, 2009—San Francisco, California

                  Filed December 3, 2009

   Before: Mary M. Schroeder, A. Wallace Tashima and
            Marsha S. Berzon, Circuit Judges.

                            15823
15824   SOUTH FORK BAND v. DOI
         Per Curiam Opinion
15826             SOUTH FORK BAND v. DOI




                        COUNSEL

Roger Flynn, Lyons, Colorado, for the plaintiffs-appellants.

Francis M. Wikstrom, Salt Lake City, Utah, for defendant-
appellee Barrick Cortez, Inc.

Sambhav N. Sankar, Washington, D.C., for defendant-
appellee U.S. Department of Interior.
                   SOUTH FORK BAND v. DOI                 15827
                          OPINION

PER CURIAM:

   This is an appeal from the denial of a preliminary injunc-
tion in an environmental challenge to a major gold mining
project on the side of Mt. Tenabo in Nevada. The mountain
has religious significance for Indian tribes.

   The plaintiffs-appellants are the South Fork Band Council
of Western Shoshone of Nevada, and other tribes and organi-
zations (“the Tribes”). The Tribes originally filed this action
against the United States Department of the Interior and its
Bureau of Land Management (“BLM”) after BLM issued its
final environmental impact statement approving the project.
The project’s developer, Barrick Cortez, Inc., (“Cortez”)
appeared as an intervenor and is also an appellee.

   This court denied the Tribes’ emergency motion for an
injunction pending appeal, but expedited the briefing and
argument of the appeal. The district court’s opinion is pub-
lished at South Fork Band v. U.S. Dep’t of Interior, __ F.
Supp. 2d ___, No. 3:08-cv-00616, 2009 WL 249711 (D. Nev.
Feb. 3, 2009), and devotes most of its consideration to claims
brought under the Religious Freedom Restoration Act
(“RFRA”), 42 U.S.C. §§ 2000bb-2000bb-4. These claims are
not pursued on appeal.

   Before us are claims alleging violations of the Federal Land
Policy Management Act (“FLPMA”), 43 U.S.C. §§ 1701 et
seq., and the National Environmental Policy Act (“NEPA”),
42 U.S.C. §§ 4321 et seq. In determining whether a prelimi-
nary injunction should issue, we are bound by the Supreme
Court’s recent opinion in Winter v. Natural Res. Def. Council,
129 S. Ct. 365 (2008). We must decide whether the Tribes
have shown that they are likely to succeed on the merits of
their claims; that they are likely to suffer irreparable harm if
a preliminary injunction is denied; that the balance of the
15828               SOUTH FORK BAND v. DOI
equities tips in their favor; and that an injunction is in the pub-
lic interest. Id. at 374. The Tribes must make each of these
showings to be entitled to injunctive relief. Id. at 374-76.

   To succeed on the merits of their action under the Adminis-
trative Procedure Act, the Tribes must show that BLM’s
action was arbitrary and capricious or contrary to law. See 5
U.S.C. § 706(2)(A); see also Motor Veh. Mfrs. Ass’n v. State
Farm Mut. Ins. Co., 463 U.S. 29, 43 (1983). Given the thor-
ough consideration of the project’s impact on the Tribes reli-
gion in the Environmental Impact Statement (“EIS”), which
was approved after more than two years of study and consul-
tation with the Tribes and with the public, we conclude that
the Tribes have not satisfied their burden of showing a likeli-
hood of success on the merits of their FLPMA claims. We
reverse the denial of injunctive relief on the NEPA claims,
however, and remand for the entry of an injunction pending
preparation of an EIS that adequately considers the environ-
mental impact of the extraction of millions of tons of refrac-
tory ore, mitigation of the adverse impact on local springs and
streams, and the extent of fine particulate emissions.

            Factual and Procedural Background

   This appeal concerns a proposed gold mining project in the
Cortez Mining District, located in Lander County, Nevada on
and near Mt. Tenabo, a Western Shoshone sacred site. Gold
mining has been a dominant industry in Lander County since
the 1950s, and the Cortez Mine has been in operation since
1968. Between 1999 and 2004, miners identified two new
gold sources near Cortez’s existing mining operations. In
2005, Cortez submitted a proposal for the Cortez Hills Expan-
sion Project, which would extend Cortez’s mining activities to
the areas of the newly-discovered deposits. As originally pro-
posed by Cortez, the project would have involved ten years of
active mining and up to three years of ore processing, fol-
lowed by site closure and reclamation. The specific activities
Cortez proposed included digging a new 850-acre mine pit;
                   SOUTH FORK BAND v. DOI                  15829
adding facilities for cyanide heap-leach processing; adding
areas for disposal of approximately 1.5 billion tons of waste
rock; upgrading its mine dewatering systems to remove sur-
face and ground water that would otherwise fill the mines;
and building and operating a twelve-mile ore-hauling con-
veyor system. The project as originally proposed would have
disturbed 6,792 acres within the 57,058-acre project bound-
ary. Of the disturbed acreage, 6,571 acres were public land
and 221 acres were private land belonging to Cortez.

   After Cortez’s proposal was submitted, BLM determined
that it constituted a “major federal action” for which NEPA
required the preparation of an EIS, and that the project was
also subject to FLPMA. BLM published a Notice of Intent to
Prepare an EIS in December 2005, and over the following two
years, BLM studied the potential impacts of the project and
consulted with South Fork and other local tribes. BLM pub-
lished a Draft EIS on October 5, 2007, which evaluated five
alternatives: Cortez’s proposal, three action alternatives not at
issue in this appeal, and a no-action alternative in which Cor-
tez would continue its current mining activities without fur-
ther expansion. The Draft EIS evaluated these alternatives in
light of their impacts on: (1) geology and minerals; (2) water;
(3) soils; (4) vegetation; (5) wildlife; (6) woodlands; (7) range
resources; (8) paleontology; (9) Native American cultural
resources; (10) Native American values; (11) air quality; (12)
land use and access; (13) recreation; (14) social and economic
values; (15) environmental justice; (16) visual resources; (17)
noise; and (18) hazardous materials and solid waste.

   After receiving public comments on the Draft EIS, BLM
developed and evaluated a fourth action alternative known as
the “Revised Cortez Hills Pit Design Alternative.” Described
in the Final EIS (“FEIS”) published on October 3, 2008, this
alternative involved smaller expansions to Cortez’s existing
mining pits and waste rock disposal areas, a larger under-
ground mining component, and smaller heap-leach facilities.
15830              SOUTH FORK BAND v. DOI
   BLM’s Record of Decision (“ROD”), published on Novem-
ber 12, 2008, adopted the Revised Cortez Hills Pit Design
Alternative and required Cortez to comply with the environ-
mental protection measures described in Cortez’s original
proposal and with all mitigation measures listed in the FEIS.
The agency concluded that, with these safeguards, there
would be no “unnecessary or undue degradation of the public
lands,” and therefore no violation of FLPMA. FLPMA pro-
vides in relevant part that agencies such as BLM must take
action to prevent “unnecessary or undue degradation,” which
is defined as harm to the environment that is either unneces-
sary to a given project or violates specified environmental
protection statutes. See 43 U.S.C. § 1732(b); 43 C.F.R.
§ 3809.5.

   On November 20, 2008, the Tribes filed a complaint
against the Department of the Interior and BLM in the District
of Nevada. Cortez intervened as a defendant. The Tribes
moved for a preliminary injunction. After holding a hearing,
the district court first issued a denial from the bench and then
filed a published opinion denying the injunction on February
3, 2009. See South Fork Band, 2009 WL 249711.

  The Tribes filed a Notice of Appeal on February 6, 2009,
and a few days later, the district court denied South Fork’s
motion for a stay pending appeal. On February 18, 2009, this
court denied an emergency motion for an injunction pending
appeal, but ordered briefing and argument expedited.

                          Discussion

  I.    FLPMA Claims

   The primary claims that the Tribes presented in the district
court related to the exercise of their religion. The Tribes
claimed in the main that the project would violate RFRA
because it would create a substantial burden to the exercise of
their religion. RFRA prohibits governmental entities from
                   SOUTH FORK BAND v. DOI                  15831
imposing substantial burdens on the exercise of religion, even
if such burdens arise from a rule of general applicability,
unless the government can demonstrate that the rule is both in
furtherance of a compelling governmental interest and the
least restrictive means of furthering that interest. 42 U.S.C.
§ 2000bb-1(a)-(b). Although the district court agreed with the
Tribes that they had standing to bring the RFRA claim and
that RFRA applies to the use and management of the govern-
ment’s own land, see South Fork Band, 2009 WL 249711, at
*4-12, the court denied the RFRA claims on the merits, con-
cluding that the Tribes had not shown there was a likelihood
of success of establishing a substantial burden on the exercise
of the Tribes’ religion, id. at *12-14. The court stressed that
the Tribes would continue to have access to the areas that
were identified during consultation with the Tribes as having
the most religious significance. The Tribes have not appealed
the denial of preliminary injunctive relief on the RFRA
claims.

   [1] The Tribes do appeal the denial of injunctive relief on
a FLPMA claim that is substantially the same as the RFRA
claim, but is cast in procedural rather than substantive terms.
See Norton v. S. Utah Wilderness Alliance, 542 U.S. 55, 66
(2004); Gros Ventre Tribe v. United States, 469 F.3d 801, 814
(9th Cir. 2006) (“The FLPMA is primarily procedural in
nature, and it does not provide a private right of action.”).
FLPMA creates a duty on the part of agencies like BLM to
take action to prevent “unnecessary and undue degradation of
the lands.” 43 U.S.C. § 1732(b). For the purposes of this case,
“unnecessary or undue degradation” is defined as any harmful
activity that is either not “reasonably incident” to an approved
mining operation or that violates a state or federal law relating
to environmental or cultural resource protection. 43 C.F.R.
§ 3809.5.

  [2] To support the FLPMA claim, the Tribes rely heavily
upon Executive Order No. 13007 (“EO 13007”), which
imposes an obligation on the Executive Branch to accommo-
15832               SOUTH FORK BAND v. DOI
date Tribal access and ceremonial use of sacred sites and to
avoid physical damage to them. See 61 Fed. Reg. 26771 (May
24, 1996). The district court expressly recognized that BLM
was required to comply with the Executive Order. South Fork
Band, 2009 WL 249711, at *16 n.9. After reviewing the
extensive study that the agency had made of the sacred sites
and their uses, however, the court concluded that the Tribes
failed to show BLM’s conduct of the study was arbitrary, or
that BLM violated any duty under EO 13007 when it found
the project would neither harm areas identified during the
study as sacred, nor materially affect access to those areas. Id.

   In this appeal from the denial of injunctive relief, the Tribes
do not question the sufficiency of BLM’s consultation with its
tribal consultants or the adequacy of BLM’s study of the
potential effects of the project on the Tribes’ religious uses
and practices. The Tribes contend that, on the basis of its con-
sultation and study, the BLM arbitrarily focused on the spe-
cific sites identified during the study. According to the Tribes,
the BLM should have treated the entire mountain as sacred to
the Tribes.

   It is true that the extensive record of consultation with the
Tribes contains references to the entire mountain as being a
sacred site. There are, however, many more specific refer-
ences to the particular sites on the mountain that are used for
religious observance. These significant sites include the top of
the mountain, the White Cliffs immediately below the top of
the mountain, the Pediment area of piñon-juniper groves on
the slope of the mountain, the Shoshone Wells, and the Horse
Canyon.

   [3] In the EIS, BLM concluded that access to and use of
those more discrete sites for cultural and religious observance
would not be impeded by the project as approved, and the
Tribes do not dispute that conclusion. The Tribes also do not
articulate the manner in which they seek agency accommoda-
tion for the entire mountain. EO 13007 refers to protecting the
                    SOUTH FORK BAND v. DOI                 15833
ceremonial uses of sacred sites. See Fed. Reg. 26771 (May 24,
1996) (agencies shall “accommodate access to and ceremonial
use of Indian sacred sites by Indian religious practitioners and
. . . avoid adversely affecting the physical integrity of such
sacred sites.”)

   Not only did the study of the project’s effects extend over
two years, but the EIS devoted over seventy pages to its dis-
cussion of BLM’s consultation with the Tribes concerning
their religious practices. As a result of BLM’s consultation
and recognition of the need to accommodate religious prac-
tices, the original scope of the project was reduced. Moreover,
and significantly, the EIS stated that the BLM would continue
consulting with the Tribes regarding the project’s impact on
their religious practices throughout the life of the project.

   [4] We see no basis to disturb the district court’s conclusion
that the Tribes failed to demonstrate a likelihood of success
in establishing any arbitrary or capricious agency action in
relation to BLM’s obligation under EO 13007 to accommo-
date the Tribes’ need for access to and use of religious sites.

   The Tribes’ remaining FLPMA claim is that BLM acted
arbitrarily and capriciously by failing to find an unnecessary
or undue degradation of scenic resources as a result of the
mining operation. According to the record, BLM has a four-
level system of classifying visual impacts due to mining proj-
ects. Class I areas are the most highly protected areas, while
Class IV areas allow the most visual impact.

   [5] The areas affected by the mining project in this case
were designated by BLM as belonging to Classes III and IV.
BLM determined that some of the mining facilities would sat-
isfy the visual impact standards associated with their particu-
lar classification, either during the life of the project or after
reclamation of the site. Other facilities, however, were
deemed unlikely to meet the relevant visual impact standards,
but the agency determined that the adverse visual impacts
15834              SOUTH FORK BAND v. DOI
were not significant enough to justify disapproving the proj-
ect. The Tribes fail to point to any relevant action on BLM’s
part that was arbitrary or unreasonable. We will not second-
guess the agency’s weighing of the compliant and non-
compliant visual resource areas in light of its experience and
expertise. Trout Unlimited v. Lohn, 559 F.3d 946, 955 (9th
Cir. 2009). We affirm the district court’s determination that
the Tribes failed to show a likelihood of succeeding on their
FLPMA claims.

  II.   NEPA Claims

   [6] NEPA requires that all federal agencies prepare, for
every major federal action significantly affecting the quality
of the human environment, a “detailed statement . . . on . . .
the environmental impact of the proposed action.” 42 U.S.C.
§ 4332(C). An adequate EIS is essential to informed agency
decision-making and informed public participation, without
which the environmental objectives of NEPA cannot be
achieved. See 42 U.S.C. § 4331(A); Robertson v. Methow
Valley Citizens Council, 490 U.S. 332, 348 (1989) (discussing
NEPA’s effort to infuse “a broad national commitment to pro-
tecting and promoting environmental quality” into “the ongo-
ing programs and actions of the Federal Government”).

                     Ore Transportation

   The Tribes claim BLM violated NEPA by failing to ana-
lyze the air quality impacts of the transportation of ore to an
off-site processing facility. BLM estimates in the EIS that this
mine expansion will make five million tons of refractory ore
available for extraction. It will be transported 70 miles to the
Goldstrike facility for processing, in two shipments per day,
every day, for ten years. The processing of that refractory ore
will result in the release of some quantity of mercury, a haz-
ardous air pollutant. The transport of the ore, the Tribes
allege, will negatively impact air quality. BLM now main-
tains, nonetheless, that these environmental impacts need not
                       SOUTH FORK BAND v. DOI                        15835
be discussed in the EIS, because no increase in the rate of
toxic ore shipments is proposed, and the off-site facility is
permitted under the Clean Air Act.

   [7] The air quality impacts associated with transport and
off-site processing of the five million tons of refractory ore
are prime examples of indirect effects that NEPA requires be
considered. The Council on Environmental Quality regula-
tions define indirect effects as those “caused by the action,
[and] later in time or further removed in distance, [but] still
reasonably foreseeable.” 40 C.F.R. § 1508.8(b). An agency
must consider them. 40 C.F.R. § 1502(b).

   BLM is incorrect in asserting that these effects need not be
considered simply because no change in the rate of shipping
and processing is forecast. That may be so, but the mine
expansion will create ten additional years of such transporta-
tion that is, ten years of environmental impacts that would not
be present in the no-action scenario.

   Moreover, even on a year-to-year basis, there has been no
consideration of the environmental impact of the transporta-
tion and processing of the refractory ore. BLM’s argument to
the contrary depends on the assumption that, because off-site
processing is ongoing, these impacts must have been analyzed
in a NEPA document already. But that assumption is baseless:
there is no indication that these impacts were properly consid-
ered at any time, even on a year-to-year basis.

   Appellees make several arguments in defense of the omis-
sion. First, Cortez asserts that the mercury impacts are dis-
cussed in the EIS, citing a map that shows aggregated
mercury emissions from all gold mines in the state as a per-
centage of total mercury emissions. A close examination of
the EIS belies the claim. The EIS does not indicate that BLM
accounted for the mercury emissions of the separately owned,
off-site Goldstrike facility in preparing this analysis.1 In any
  1
   To the contrary, it states that "the area for air quality encompasses the
area within the project boundary and the area within 10 kilometers (km)
15836                 SOUTH FORK BAND v. DOI
event, the cited figure sheds no light on the specific effect at
issue—the environmental impact of processing ore from this
project. See Klamath-Siskiyou Wildlands Center v. BLM, 387
F.3d 989, 997 (9th Cir. 2004) (holding that a general discus-
sion of an environmental problem across a large area did not
satisfy NEPA).

   In the alternative, Cortez asserts that the draft EIS for a dif-
ferent mine expansion—the Betze Pit Expansion—satisfies
BLM’s responsibilities under NEPA. It does not suffice. Cor-
tez does not show that any effects of the Cortez expansion
were considered in the Betze EIS. We have never held that the
analysis of similar effects for a separate project excuses the
failure to consider significant environmental impacts in an
EIS. Though “tiering” to a previous EIS is sometimes permis-
sible, the previous document must actually discuss the
impacts of the project at issue. Muckleshoot Indian Tribe v.
U.S. Forest Service, 177 F.3d 800, 810 (9th Cir. 1999) (hold-
ing that reliance on the EIS accompanying an earlier planning
document was improper because it did not discuss the subse-
quent specific project in detail). The mere existence of an
entirely separate draft EIS, discussing a similar issue with
regard to a different project, but without any indication that
it discussed the specific environmental impacts at issue, can-
not satisfy NEPA.

   Finally, BLM argues that the off-site impacts need not be
evaluated because the Goldstrike facility operates pursuant to
a state permit under the Clean Air Act. This argument also is
without merit. A non-NEPA document—let alone one pre-
pared and adopted by a state government—cannot satisfy a
federal agency’s obligations under NEPA. Klamath-Siskiyou
Wildlands Center v. BLM, 387 F.3d 989, 998 (9th Cir. 2004).

(6.2 miles) of the proposed project. The cumulative effects study area
encompasses the Crescent Valley and Grass Valley hydrographic basins."
The Goldstrike facility, located 70 miles away, and north of the Humboldt
River, is outside of the "study area."
                   SOUTH FORK BAND v. DOI                  15837
  [8] BLM’s failure to consider the transport and processing
of five million tons of refractory ore over a ten-year period
shows that it did not take the requisite “hard look” at the envi-
ronmental impacts of the proposed project.

                      Mine Dewatering

   The Tribes contend the BLM failed to conduct an appropri-
ate mitigation analysis with respect to the environmental con-
sequences of mine dewatering. The extensive removal of
groundwater implicit in this project is expected to cause some
number of local springs and streams to dry up. At least fifteen
springs are not expected to recover within 100 years.

   [9] As the EIS concedes, these are significant environmen-
tal harms. Though NEPA, of course, does not require that
these harms actually be mitigated, it does require that an EIS
discuss mitigation measures, with “sufficient detail to ensure
that environmental consequences have been fairly evaluated.”
Methow Valley, 490 U.S. at 352.

   [10] An essential component of a reasonably complete miti-
gation discussion is an assessment of whether the proposed
mitigation measures can be effective. Compare Neighbors of
Cuddy Mountain v. U.S. Forest Service, 137 F.3d 1372, 1381
(9th Cir. 1998) (disapproving an EIS that lacked such an
assessment) with Okanogan Highlands Alliance v. Williams,
236 F.3d 468, 477 (9th Cir. 2000) (upholding an EIS where
“[e]ach mitigating process was evaluated separately and given
an effectiveness rating”). The Supreme Court has required a
mitigation discussion precisely for the purpose of evaluating
whether anticipated environmental impacts can be avoided.
Methow Valley, 490 U.S. at 351-52 (citing 42 U.S.C.
§ 4332(C)(ii)). A mitigation discussion without at least some
evaluation of effectiveness is useless in making that determi-
nation.

   [11] Although the District Court’s written order finds that
the EIS discusses the effectiveness of each mitigation mea-
15838              SOUTH FORK BAND v. DOI
sure, close inspection reveals that the EIS does not in fact
assess the effectiveness of the mitigation measures relating to
groundwater. It states only, “Feasibility and success of mitiga-
tion would depend on site-specific conditions and details of
the mitigation plan.” Nothing whatsoever is said about
whether the anticipated harms could be avoided by any of the
listed mitigation measures. This discussion is inadequate.

   BLM argues that an effectiveness discussion was not
required because it is impossible to predict the precise loca-
tion and extent of groundwater reduction, and that problems
should instead be identified and addressed as they arise. But
NEPA requires that a hard look be taken, if possible, before
the environmentally harmful actions are put into effect.
National Parks & Conservation Association v. Babbitt, 241
F.3d 722, 733 (9th Cir. 2001).

   [12] In this instance, the EIS states that BLM has identified
fifty perennial springs and one perennial creek that are the
most likely to dry up, though among these it is impossible to
“conclusively identify specific springs and seeps that would
or would not be impacted.” That these individual harms are
somewhat uncertain due to BLM’s limited understanding of
the hydrologic features of the area does not relieve BLM of
the responsibility under NEPA to discuss mitigation of rea-
sonably likely impacts at the outset. See National Parks, 241
F.3d at 733 (“lack of knowledge does not excuse the prepara-
tion of an EIS; rather it requires [the agency] to do the neces-
sary work to obtain it.”) Even if the discussion must
necessarily be tentative or contingent, NEPA requires that the
agency give some sense of whether the drying up of these
water resources could be avoided.

                    Particulate Emissions

  There is also a claim with regard to particulate emissions.
Prior to 2007, it was a common governmental environmental
practice to use PM10 emission modeling as a surrogate for
                   SOUTH FORK BAND v. DOI                  15839
determining emission of smaller PM2.5 particulate matter. In
2007, the EPA disallowed the practice. See 72 Fed. Reg.
20568, 20600 (Apr. 25, 2007). In this case, the BLM indispu-
tably did not do separate modeling for the PM2.5 emissions
when the draft EIS for the project was being prepared. It used
PM10 emissions modeling as a surrogate. When it was brought
to the BLM’s attention during the 2007 comment period that,
as of 2007, such surrogate modeling was no longer allowed
by the EPA, the BLM gave a reasoned explanation of why
separate modeling for PM2.5 emissions was not necessary
here. It said that PM2.5 emissions are generally 15% of the PM10
emissions, and that on the basis of the PM10 emission model-
ing that was conducted for this project, the PM2.5 emissions
were well within EPA tolerances. The district court concluded
that the Tribes’ challenge to the study of PM2.5 emissions
lacked any probability of success because the NEPA analysis
was thorough, and the agency responded specifically and in
detail to the comment it received on the draft EIS.

   On appeal, the Tribes stress, however, that the EPA, as
early as 2005, announced technical difficulties underlying the
surrogate modeling policy, see 70 Fed. Reg. 65984, 66043
(Nov. 1, 2005), and in 2007 renounced the use of PM10 partic-
ulate emissions as a surrogate for PM2.5 emissions. The Tribes
contend that the BLM’s reliance on the surrogate analysis was
contrary to 2007 EPA requirements, and thus contrary to law.

   [13] The study that BLM did for this project was in large
part conducted before 2007, when the surrogate analysis it
used was appropriate. Because the BLM must revise its study
of the environmental consequences of this project as a result
of this litigation, it should do separate modeling for PM2.5 par-
ticulate emissions.

                     Scope of Injunction

  [14] For the foregoing reasons, we agree with the district
court that the Tribes have not established a likelihood of suc-
15840               SOUTH FORK BAND v. DOI
cess on the merits of their FLPMA claims, but hold they have
established a likelihood of success on the NEPA claims. Such
a showing is required for a grant of preliminary injunctive
relief. In addition, the party seeking such relief must establish
that it “is likely to suffer irreparable harm in the absence of
preliminary relief that the balance of equities tips in his favor,
and that an injunction is in the public interest.” Winter, 1295
S.Ct. 374. Plaintiffs have shown a likelihood of success on the
NEPA claims because there was inadequate study of the seri-
ous effects of processing refractory ore and exhausting scarce
water resources. The likelihood of irreparable environmental
injury without adequate study of the adverse effects and pos-
sible mitigation is high. Indeed the district court did not ques-
tion the irreparable environmental harm threatened by this
massive project, and that will be visited most directly on the
plaintiffs. The resulting hardship asserted by Cortez and the
government is cast principally in economic terms of employ-
ment loss, but that may for the most part be temporary. Given
the narrow scope of our holding, which rejects the broader
FLPMA contentions, the balance of hardship favors the appel-
lants. As to the public interest, Congress’s determination in
enacting NEPA was that the public interest requires careful
consideration of environmental impacts before major federal
projects may go forward. Suspending a project until that con-
sideration has occurred thus comports with the public interest.

                          Conclusion

   The order of the district court denying preliminary injunc-
tive relief is AFFIRMED in part and REVERSED in part. The
matter is REMANDED for entry of injunctive relief consis-
tent with this opinion with each party to bear its own costs.
