                        PUBLISHED


UNITED STATES COURT OF APPEALS
              FOR THE FOURTH CIRCUIT


PAT WEBSTER; JOEM WEBSTER;              
ELIZABETH WEBSTER; CHARLES
FOLTZ; LINDA FOLTZ; GLORIA FOLTZ
WALKER; ELIZABETH WEBSTER, as
Executrix for the Estate of Allaina
Garrett Whetzel,
               Plaintiffs-Appellants,
                 v.
UNITED STATES DEPARTMENT OF                 No. 11-1739
AGRICULTURE, by and through its
Agency, the Natural Resources
Conservation Service; POTOMAC
VALLEY CONSERVATION DISTRICT;
HARDY COUNTY COMMISSION; WEST
VIRGINIA STATE CONSERVATION
AGENCY,
             Defendants-Appellees.
                                        
        Appeal from the United States District Court
    for the Northern District of West Virginia, at Elkins.
          John Preston Bailey, Chief District Judge.
                    (2:09-cv-00138-JPB)

                   Argued: May 16, 2012

                   Decided: July 13, 2012

      Before WILKINSON, GREGORY, and FLOYD,
                    Circuit Judges.
2                         WEBSTER v. USDA
Affirmed by published opinion. Judge Floyd wrote the opin-
ion, in which Judge Wilkinson and Judge Gregory joined.


                              COUNSEL

ARGUED: Christopher Patrick Stroech, Shepherdstown,
West Virginia, for Appellants. Mark R. Haag, UNITED
STATES DEPARTMENT OF JUSTICE, Washington, D.C.,
for Appellees. ON BRIEF: Silas B. Taylor, OFFICE OF THE
WEST VIRGINIA ATTORNEY GENERAL, Charleston,
West Virginia, for Appellee West Virginia State Conservation
Agency; Jessica M. Baker, WALTERS, KRAUSKOPF &
BAKER, Moorefield, West Virginia, for Appellees Potomac
Valley Conservation District and Hardy County Commission;
Ignacia S. Moreno, Assistant Attorney General, Elizabeth
Ann Peterson, Environment & Natural Resources Division,
UNITED STATES DEPARTMENT OF JUSTICE, Washing-
ton, D.C., for Appellee United States Department of Agricul-
ture.


                              OPINION

FLOYD, Circuit Judge:

  Over thirty-five years ago, the Natural Resources Conser-
vation Service (NRCS),1 working with local sponsors, devised
a project to provide watershed protection, flood prevention,
and recreation along the Lost River Subwatershed. The pro-
posed project involved a combination of land-treatment mea-
sures and five dams and impoundments. In 1974, the NRCS
   1
     The NRCS is an agency of the United States Department of Agricul-
ture (USDA). Its predecessor agency until 1994 was the Soil Conservation
Service. Holly Hill Farm Corp. v. United States, 447 F.3d 258, 260 n.1
(4th Cir. 2006). For ease of reference, we consistently refer to the agency
as the "NRCS."
                      WEBSTER v. USDA                         3
issued an environmental impact statement relating to the proj-
ect, and since that time, three dams and most of the land-
treatment measures have been completed. After preparing a
supplemental environmental impact statement in 2009, the
NRCS issued a record of decision that eliminated one of the
remaining dams from the project and authorized construction
of the final dam for the added purpose of providing water sup-
ply. Appellants, seven individuals who allege that their land
will be adversely affected by this final dam’s construction,
filed this action contending that the NRCS has failed to com-
ply with the National Environmental Policy Act (NEPA).
They now appeal the district court’s order granting Appellees’
motion for summary judgment. Because we determine that the
NRCS has complied with the procedures mandated by the
NEPA and taken a hard look at the project’s environmental
effects, we affirm.

                               I.

                              A.

   The "NEPA is a procedural statute" that "sets forth a regu-
latory scheme for major federal actions that may significantly
affect the natural environment." Nat’l Audubon Soc’y v. Dep’t
of the Navy, 422 F.3d 174, 184 (4th Cir. 2005). Its procedural
mandates serve dual purposes. Id. They ensure that an agency
planning a major federal action obtains and considers the nec-
essary information concerning any significant environmental
impacts that the action may cause. Hodges v. Abraham, 300
F.3d 432, 438 (4th Cir. 2002). They also guarantee that the
public has access to the relevant information about the pro-
posed action so that it can participate in the decisionmaking
process. Id.

  Under the NEPA, every "federal agency contemplating a
major action" must formulate an environmental impact state-
ment (EIS) if the action could significantly affect the environ-
ment. Robertson v. Methow Valley Citizens Council, 490 U.S.
4                      WEBSTER v. USDA
332, 349 (1989); see also 42 U.S.C. § 4332(C). An EIS must
contain certain information specified by federal statute and
regulations promulgated by the Council of Environmental
Quality (CEQ), a governmental body created by the NEPA.
Nat’l Audubon Soc’y, 422 F.3d at 184-85; Hodges, 300 F.3d
at 438. This information includes "the environmental effects
and impacts of the proposed action, reasonable alternatives to
it, possible mitigation measures for any negative environmen-
tal impacts that will result from it, and the cumulative impacts
of it combined with other past, present, or foreseeable future
actions." Nat’l Audubon Soc’y, 422 F.3d at 185 (citations
omitted).

   When preparing an EIS, an agency must follow procedures
established by the CEQ. Id. These procedures require that an
agency draft an EIS in stages. Id. The process begins with the
agency publishing in the Federal Register a notice of intent to
prepare and consider an EIS. 40 C.F.R. §§ 1501.7, 1508.22.
Then the agency must engage in a "scoping" process designed
to determine the scope of the issues to be addressed in the EIS
and to identify significant issues related to the proposed
action. Id. § 1501.7. During the scoping process, the agency
must, among other things, invite participation and input by
federal, state, and local agencies, as well as the public. Id.; see
also Citizens’ Comm. to Save Our Canyons v. U.S. Forest
Serv., 297 F.3d 1012, 1022 (10th Cir. 2002). Utilizing infor-
mation acquired during the scoping process, the agency is
then to prepare an initial draft EIS, which it must make pub-
licly available and circulate to other agencies for feedback. 40
C.F.R. §§ 1502.9(a), 1503.1. After doing so, the agency must
draft a final EIS that addresses any comments. Id.
§§ 1502.9(b), 1503.4.

   Under certain circumstances, after the issuance of a final
EIS, the agency may draw up a supplemental EIS. It may pre-
pare a supplemental EIS if it determines that doing so would
further the purposes of the NEPA. Id. § 1502.9(c)(2). A sup-
plemental EIS becomes mandatory if the agency "makes sub-
                      WEBSTER v. USDA                         5
stantial changes in the proposed action that are relevant to
environmental concerns" or if "significant new circumstances
or information relevant to environmental concerns and bear-
ing on the proposed action or its impacts" arise. Id.
§ 1502.9(c)(1). The agency must prepare, circulate, and file a
supplemental EIS in the same manner as draft and final EISs,
except, in general, it need not undertake a scoping process. Id.
§ 1502.9(c)(4). But if the agency makes substantial changes to
the proposed action or significant new circumstances or infor-
mation bearing on the proposal or its impacts arise, the
agency must revise the determinations reached in the initial
scoping process. Id. § 1501.7(c).

   Finally, after the agency makes a decision regarding the
action, it must publish a record of decision, at which point it
may then finalize its action. Nat’l Audubon Soc’y, 422 F.3d
at 185. As a purely procedural statute, the NEPA "does not
mandate particular results, but simply prescribes the necessary
process." Robertson, 490 U.S. at 350. In that sense, "it does
not force an agency to reach substantive, environment-
friendly outcomes," meaning that as long as the agency ade-
quately considers a proposed project’s adverse environmental
effects, it may choose to pursue the project if it decides that
the benefits outweigh them. Nat’l Audubon Soc’y, 422 F.3d at
184. Simply put, the "NEPA merely prohibits unin-
formed—rather than unwise—agency action." Robertson, 490
U.S. at 351.

   With this regulatory framework in mind, we now address
the underlying events giving rise to this appeal.

                              B.

   In December 1944, Congress enacted the Flood Control
Act of 1944, ch. 665, 58 Stat. 887, authorizing "the construc-
tion and operation of certain dam and reservoir projects."
Cent. Elec. Power Coop., Inc. v. Se. Power Admin., 338 F.3d
333, 335 (4th Cir. 2003). Among the authorized projects were
6                         WEBSTER v. USDA
"works of improvement for run-off and waterflow retardation,
and soil-erosion prevention" for various specified watersheds,
including the Potomac River Watershed. 58 Stat. at 905-06.
The dispute here involves a project on the Lost River Sub-
watershed, a part of the Potomac River Watershed situated in
Hardy County, West Virginia.

   Pursuant to this grant of authority, the NRCS, upon appli-
cation by local sponsoring organizations,2 developed the "Lost
River Subwatershed Project" (Project). In October 1974, after
circulating a draft for comment, the NRCS issued a final EIS
(1974 EIS) related to the Project. In it, the NRCS observed
that the Lost River Subwatershed was incurring damage from
erosion, sedimentation, and frequent floods. It also recognized
the need for more recreational opportunities in the area. The
NRCS thus identified three overarching purposes underlying
the Project: watershed protection, flood prevention, and recre-
ation.

   Additionally, in the 1974 EIS, the NRCS analyzed six alter-
natives, including the alternative of no action, before settling
on a plan that involved applying land-treatment measures to
94,750 acres and constructing five dams and impoundments
on designated sites. Four of the dams, located on Sites 4, 10,
23, and 27, were to be single-purpose flood-retarding struc-
tures. The fifth dam, located on Site 16, was to be a multiple-
purpose floodwater storage and recreation structure. The
NRCS described the Project’s anticipated environmental
impacts and recognized that it would require relocating eleven
residences. The NRCS also considered and responded to com-
ments received by various governmental agencies.
    2
   Originally, the local project sponsors consisted of the County Court of
Hardy County and the Potomac Valley Conservation District (PVCD). As
the Project progressed, the Hardy County Commission (HCC) replaced the
County Court as a sponsor. The West Virginia State Conservation Com-
mittee, which is the governing board of directors of the West Virginia
State Conservation Agency (WVSCA), also later joined.
                       WEBSTER v. USDA                         7
   Also in October 1974, the NRCS and the local project
sponsors released a work plan for implementing the Project.
They discovered, however, that local support for the Project
was lacking, prompting them to suspend its implementation.
In 1977, the NRCS noted in a letter that revival of the Project
would primarily depend on a decision by the local sponsors
to proceed. After serious flooding in 1985 caused damage
along the Lost River, the project sponsors requested that the
NRCS resume implementation of the Project, so it did.

   In August 1989, the NRCS issued an environmental assess-
ment (1989 EA), which is a document that an agency prepares
to assist its planning and decisionmaking or to determine
whether an EIS is necessary, 40 C.F.R. §§ 1501.3, 1501.4(c).
In the 1989 EA, the NRCS reevaluated potential environmen-
tal impacts relating to Site 4, the first dam scheduled for con-
struction. A little over a year later, the NRCS drafted a
"Supplemental Information Report" analyzing whether there
had been any significant changes to the Project as a whole or
whether any significant environmental changes had occurred
since issuance of the 1974 EIS. It concluded that there had
been no such changes and determined that the 1974 EIS still
adequately described the Project and its impacts. Neverthe-
less, in this report, the NRCS addressed some insignificant
environmental changes and changes with respect to the costs,
benefits, and opportunities for incidental recreation.

   The NRCS issued a record of decision in January 1991
approving implementation of the Project. A federal lawsuit
was then brought challenging the Project and the planned con-
struction of the dam at Site 4, but the parties ultimately agreed
to dismiss the claims involving Site 4 with prejudice and the
claims challenging the remainder of the sites without preju-
dice. In May 1994, as Site 4’s dam was under construction,
the NRCS issued an environmental information report relating
to the next dam scheduled for construction, the Site 27 dam.
By 2001, construction of the dams on Sites 4 and 27 was
8                     WEBSTER v. USDA
complete, and land-treatment measures had been applied to
16,740 acres in accordance with the Project.

   The NRCS then turned its attention to construction of the
dam at Site 10. In 2001, it issued an environmental assess-
ment report (2001 EA) primarily addressing this dam’s
planned construction. The NRCS discussed a recent drought
in the area that prompted the local sponsors to request that it
add water supply as a purpose for the Site 10 dam. It evalu-
ated the need for this additional purpose and the resultant
effects of such a change. The NRCS considered three alterna-
tives involving the use of surface water, groundwater, and
water purchase agreements before concluding that adding
water supply storage to the dam at Site 10 was the only practi-
cable alternative for providing both water supply and flood
prevention.

   The Hardy County Public Service District (HCPSD),
though not a local sponsor of the Project, began planning the
construction of the "Baker/Mathias Water Distribution Sys-
tem" as early as October 2003, when it released a preliminary
engineering report. The purpose of the system, which the
USDA agreed to fund partially, was to supply water to the
central region of Hardy County. To do so, it would utilize the
water supply source from the dam at Site 10. Although con-
struction of Site 10’s dam was complete by 2005, as of 2009,
construction of the water distribution and treatment system
remained pending.

   Meanwhile, the NRCS and the local project sponsors con-
tinued to evaluate Hardy County’s water resources. In April
2004, the NRCS and the WVSCA prepared a report entitled
"Hardy County Water Resources Assessment," which evalu-
ated the existing and projected water needs for Hardy County.
Also, in March 2007, the local project sponsors, with assis-
tance from the NRCS, issued a report entitled "Projected
Water Needs in Hardy County." This report concluded that
                       WEBSTER v. USDA                         9
adding water supply storages to the dams at Sites 10 and 16
was necessary to meet the projected short-term water demand.

   In 2005 the local project sponsors requested that the NRCS
add water supply and remove recreation as purposes for Site
16’s dam. That same year, the NRCS issued a report
reevaluating Site 23 and proposing its elimination. The
changes to the Site 16 dam’s purposes and the proposed elimi-
nation of Site 23 required the NRCS to prepare a supplemen-
tal EIS, so in 2006 the NRCS published a notice of intent to
prepare such a statement and engaged in a scoping process. In
April 2007, after circulating a draft for comment, the NRCS
published a final supplemental EIS (2007 SEIS). The 2007
SEIS reflected changes in the purposes of the Site 16 dam to
include flood control, water supply, and watershed protection,
but not recreation. Approximately two months later, the
NRCS issued a record of decision; however, the NRCS with-
drew it almost two years later after the filing of a federal law-
suit challenging it. According to the NRCS, additional
analyses and investigations involving Site 16 had become
available, and it wanted to incorporate them into its supple-
mental EIS. The district court thereafter dismissed the federal
lawsuit pursuant to the parties’ stipulation.

   In March 2009, the NRCS published a notice of intent to
update and reissue a second draft supplemental EIS. It did not,
however, engage in another scoping process. After distribut-
ing a draft for comment, the NRCS issued a second final sup-
plemental EIS in August 2009 (2009 SEIS). In it, the NRCS
eliminated Site 23 from the Project and added water supply as
a purpose for the dam at Site 16. Although it removed recre-
ation as a purpose, it recognized that Site 16 would still offer
incidental recreational opportunities. As in the 2007 SEIS, the
purposes of Site 16’s dam were watershed protection, flood
prevention, and water supply. The NRCS considered seven-
teen alternatives for achieving these purposes, but analyzed
only two in detail, the no-action alternative and construction
of the dam at Site 16. After considering the relative impacts
10                    WEBSTER v. USDA
of these two alternatives, including cumulative impacts, the
NRCS recommended constructing the dam at Site 16 and
described measures for mitigating its adverse impacts. In
October 2009, the NRCS issued a second record of decision
agreeing to implement the Project for Site 16.

                              C.

   On November 23, 2009, Appellants filed a complaint in the
Northern District of West Virginia. Named as defendants
were the USDA, NRCS, PVCD, HCC, and WVSCA (collec-
tively, Appellees). Appellants challenged Appellees’ decision
to construct the dam at Site 16 and contended that they had
failed to comply with the NEPA. All Appellants asserted that
construction of the dam would not only affect their land, but
would cause them to lose at least some, if not all, of it. After
alleging numerous violations of the NEPA, primarily relating
to purported deficiencies in the 2009 SEIS, Appellants
requested declaratory and injunctive relief, costs, expenses,
and attorneys’ fees.

   In early 2011, the parties filed cross-motions for summary
judgment. On June 13, 2011, the district court issued an order
granting Appellees’ motion for summary judgment and deny-
ing Appellants’. It addressed each alleged NEPA violation
before concluding that Appellees complied with the NEPA by
abiding by its procedural requirements, taking a hard look at
the environmental consequences that would result from con-
struction of the dam at Site 16, and allowing for public partic-
ipation in the decisionmaking process. Appellants brought this
timely appeal.

                              II.

   We review de novo the district court’s order granting sum-
mary judgment. Henry v. Purnell, 652 F.3d 524, 531 (4th Cir.
2011) (en banc). "Summary judgment is appropriate only if
taking the evidence and all reasonable inferences drawn there-
                      WEBSTER v. USDA                        11
from in the light most favorable to the nonmoving party, ‘no
material facts are disputed and the moving party is entitled to
judgment as a matter of law.’" Id. (quoting Ausherman v.
Bank of Am. Corp., 352 F.3d 896, 899 (4th Cir. 2003)).

   In reviewing an agency’s efforts to comply with the NEPA,
our task is to ensure that it took a "hard look" at the environ-
mental consequences of the proposed action. Nat’l Audubon
Soc’y, 422 F.3d at 185. This review "requires a pragmatic
judgment whether the [EIS’s] form, content[,] and preparation
foster both informed decision-making and informed public
participation." Save the Peaks Coal. v. U.S. Forest Serv., 669
F.3d 1025, 1036 (9th Cir. 2012) (quoting Nat’l Parks & Con-
servation Ass’n v. Bureau of Land Mgmt., 606 F.3d 1058,
1072 (9th Cir. 2010)) (internal quotation marks omitted). A
hard look involves, at minimum, "a thorough investigation
into the environmental impacts of [the] action and a candid
acknowledgement of the risks that those impacts entail." Nat’l
Audubon Soc’y, 422 F.3d at 185. In conducting this review,
we "may not ‘flyspeck’ [the] agency’s environmental analy-
sis, looking for any deficiency, no matter how minor." Id. at
186. Instead, we "must take a holistic view of what the agency
has done to assess environmental impact" and "examine all of
the various components of [the] agency’s environmental anal-
ysis . . . to determine, on the whole, whether the agency has
conducted the required ‘hard look.’" Id.

   Moreover, because the Administrative Procedure Act
(APA) governs our review of claims brought under the
NEPA, we may set aside the agency’s action only if it is "ar-
bitrary, capricious, an abuse of discretion, or otherwise not in
accordance with law." N.C. Wildlife Fed’n v. N.C. Dep’t of
Transp., 677 F.3d 596, 601 (4th Cir. 2012) (quoting 5 U.S.C.
§ 706(2)(A)) (internal quotation marks omitted). This
involves a searching and careful, but ultimately narrow and
highly deferential, inquiry. Id.; Ohio Valley Envtl. Coal. v.
Aracoma Coal Co., 556 F.3d 177, 192 (4th Cir. 2009). In the
end, "[i]f the agency has followed the proper procedures, and
12                     WEBSTER v. USDA
if there is a rational basis for its decision, we will not disturb
its judgment." Hodges, 300 F.3d at 445.

                               III.

  On appeal, Appellants raise essentially eight issues, which
we address in turn.

                               A.

   Appellants first contend that the NRCS failed to comply
with the NEPA in arriving at watershed protection, flood pre-
vention, and water supply as its stated purposes and needs for
constructing the dam at Site 16. They maintain that the NRCS
blindly accepted the purposes and needs provided by the local
project sponsors without conducting an independent, objec-
tive inquiry. Appellants also challenge as inadequate the evi-
dence relied upon by the NRCS in justifying these purposes
and needs. As a result, they insist that the NRCS’s stated pur-
poses and needs for the dam at Site 16 are unreasonable.

   An EIS must "briefly specify the underlying purpose and
need to which the agency is responding in proposing the alter-
natives including the proposed action." 40 C.F.R. § 1502.13.
Only alternatives that accomplish the purposes of the pro-
posed action are considered reasonable, and only reasonable
alternatives require detailed study. Wyoming v. U.S. Dep’t of
Agric., 661 F.3d 1209, 1244 (10th Cir. 2011). So how the
agency defines the purpose of the proposed action sets the
contours for its exploration of available alternatives. See id.

   Agencies enjoy considerable discretion in defining the pur-
poses and needs for their proposed actions, provided that they
are reasonable. See, e.g., id. at 1244-45; Nat’l Parks & Con-
servation Ass’n, 606 F.3d at 1070; Citizens Against Burling-
ton, Inc. v. Busey, 938 F.2d 190, 196 (D.C. Cir. 1991).
Typically, a purpose is unreasonable when the agency defines
it so narrowly as to allow "only one alternative from among
                       WEBSTER v. USDA                        13
the environmentally benign ones in the agency’s power," such
that the EIS becomes essentially "a foreordained formality."
Citizens Against Burlington, 938 F.2d at 196. Conceivably, a
purpose can also be unreasonable if the agency draws it so
broadly that "an infinite number of alternatives would accom-
plish [it] and the project would collapse under the weight of
the possibilities." Id. But the potential for an agency to define
a purpose that broadly appears remote, for agencies have a
disincentive that assumedly would discourage them from
doing so: whereas drawing a purpose too narrowly is attrac-
tive because it eases the agency’s burden in drafting an EIS
by reducing the number of alternatives that it must explore in
detail, drawing a purpose too broadly complicates an agency’s
drafting of an EIS by expanding the number of alternatives it
must examine to a point that would make its task unmanage-
able.

   In deciding on the purposes and needs for a project, it is
entirely appropriate for an agency to consider the applicant’s
needs and goals. See id. Appellants, in arguing that the NRCS
inappropriately relied upon the local project sponsors’ pur-
poses and needs, seek support from the Seventh Circuit’s
decision in Simmons v. United States Army Corps of Engi-
neers, 120 F.3d 664 (7th Cir. 1997), where it stated that agen-
cies have a "duty under [the] NEPA to exercise a degree of
skepticism in dealing with self-serving statements from a
prime beneficiary of the project." Id. at 669 (quoting Citizens
Against Burlington, 938 F.2d at 209 (Buckley, J., dissenting
in part)) (internal quotation marks omitted). This decision,
however, is of no assistance to Appellants. Contrary to their
assertions, the NRCS conducted a searching, independent
review of the stated purposes and needs for Site 16’s dam,
which demonstrates that it exercised a degree of skepticism in
establishing them.

   In explaining why watershed protection and flood preven-
tion were necessary purposes and needs in the 2009 SEIS, the
NRCS incorporated by reference, among other things, the
14                    WEBSTER v. USDA
1974 EIS and work plan, which explained in detail the flood-
water, sediment, and erosion problems justifying the Project.
Furthermore, the 2009 SEIS reaffirmed the continued need for
measures to curb problems relating to flooding, noted the
almost decennial occurrence of damaging floods in the area,
and provided various maps and other investigative analyses in
support. Even if the NRCS did not provide precisely the infor-
mation that Appellants desire, it set forth enough of a well-
documented discussion to demonstrate that it had a reasonable
basis for deciding that watershed protection and flood preven-
tion were appropriate purposes and needs for Site 16’s dam.
This discussion and its accompanying information reveal that
the NRCS carefully considered including watershed protec-
tion and flood prevention as purposes and needs for the dam
at Site 16.

   Moreover, in the 2009 SEIS, the NRCS noted the local
project sponsors’ request to add water supply as a purpose and
need for the dam at Site 16, and the sponsors’ explanation of
why this addition was appropriate in light of population and
development trends and projections in the area. In recognizing
these trends and projections, the NRCS discussed the 2004
and 2007 reports on water resources in Hardy County, both of
which it assisted in preparing. Collectively, these reports sug-
gested that additional water supplies in the area were neces-
sary and that water storage in the dams at Sites 10 and 16 was
required to meet short-term demand. Although Appellants
charge that these reports have not been updated and are likely
overstated, they provide nothing beyond speculation that
would call into question their findings. Based on the NRCS’s
discussion concerning the need for water supply and the sup-
porting reports, we are confident that it adequately scrutinized
whether adding water supply as a purpose and need was
appropriate.

   On the whole, it is evident that although the NRCS consid-
ered the local project sponsors’ goals and needs, as was
appropriate, it nevertheless conducted its own searching
                      WEBSTER v. USDA                        15
inquiry into the purposes and needs for the Site 16 dam. It
then framed the purposes and needs in a manner that was nei-
ther so narrow as to yield only one suitable alternative nor so
broad as to produce an overwhelming and unmanageable
number of alternatives. And, importantly, the NRCS’s pur-
poses and needs for the dam at Site 16 are consistent with
Congress’s authorization in the Flood Control Act. See Citi-
zens Against Burlington, 938 F.2d at 196 (recognizing that
when arriving at the purposes and needs for a proposed action
agencies must consider their statutory authorization to act). In
the end, therefore, the NRCS’s decision to include watershed
protection, flood prevention, and water supply as the purposes
and needs underlying Site 16’s dam was an appropriate exer-
cise of its discretion.

                              B.

   Appellants next insist that the NRCS violated the NEPA by
failing to engage in a scoping process before issuing the 2009
SEIS. As noted, the goal of the scoping process is to "identi-
fy[ ] specific issues to be addressed and studied" by "solicit[-
ing] comments and input from the public and other state and
federal agencies." Citizens’ Comm. to Save Our Canyons, 297
F.3d at 1022. Agencies, however, are not required to engage
in a scoping process when devising a supplemental EIS, see
40 C.F.R. § 1502.9(c)(4), but they may have to revise deter-
minations made in an initial scoping process if they subse-
quently make substantial changes to the proposed action or if
significant new circumstances or information bearing on the
proposed action or its impacts arise, see id. § 1501.7(c).

   Appellants acknowledge this general rule. Their retort,
however, is that the 2009 SEIS did not supplement the 2007
SEIS but instead replaced it. Although they fail to elaborate
further, we presume their argument to be that even though the
NRCS undertook a scoping process prior to the 2007 SEIS, it
needed to undertake one leading up to the 2009 SEIS because
the 2009 SEIS replaced the 2007 SEIS. We disagree.
16                    WEBSTER v. USDA
   When it prepared the 2009 SEIS, the NRCS justifiably
relied on the scoping determinations made leading to the 2007
SEIS. That the NRCS decided to withdraw its record of deci-
sion related to the 2007 SEIS and issue the 2009 SEIS does
not operate to nullify the scoping process it had previously
undertaken. Like the 2007 SEIS before it, the 2009 SEIS sup-
plemented the 1974 EIS in light of the elimination of Site 23
and the addition of water supply as a purpose for the dam at
Site 16. As the NRCS acknowledged, the nature and extent of
the action did not change between the 2007 SEIS and the
2009 SEIS. Moreover, Appellants do not highlight any signif-
icant new circumstances or information that arose during that
time and would require revising the previous scoping determi-
nations. The specific issues that the NRCS needed to study
remained the same. Simply put, nothing occurred after the
scoping process leading to the 2007 SEIS that required the
NRCS to revisit the scoping determinations when it prepared
the 2009 SEIS.

   In the absence of any such changes or new information or
circumstances, requiring the NRCS to undertake another
scoping process for the 2009 SEIS would exact needless costs
and delay. The NEPA imposes procedural mandates for the
purpose of ensuring informed decisionmaking and public par-
ticipation, not to impose red tape for its own sake. Requiring
the NRCS to engage in a new scoping process prior to prepar-
ing the 2009 SEIS would achieve the latter consequence but
not the former purpose. We are therefore of the opinion that
the NRCS was not required to engage in another scoping pro-
cess when preparing the 2009 SEIS.

                              C.

   Appellants’ third contention is that the 2009 SEIS omits
information that is necessary for a complete analysis of the
Site 16 dam’s potential environmental impacts and stated ben-
efits. They specify a variety of missing information, mostly
pertaining to details about the construction or operation of the
                           WEBSTER v. USDA                                17
dam at Site 16. They also maintain the NRCS failed to con-
sider connected actions in the 2009 SEIS—specifically, the
construction and operation of a water treatment facility and
water distribution system.3

                                     1.

   At the outset, we reiterate that we may not seize upon triv-
ial inadequacies to reject the agency’s decision, for that would
impermissibly intrude into its decisionmaking prerogative.
Nat’l Audubon Soc’y, 422 F.3d at 186. Put another way,
"[d]eficiencies in an EIS that are mere ‘flyspecks’ and do not
defeat [the] NEPA’s goals of informed decisionmaking and
informed public comment will not lead to reversal." N.M. ex
rel. Richardson v. Bureau of Land Mgmt., 565 F.3d 683, 704
(10th Cir. 2009).

   Also, in assessing a claim that an agency has omitted infor-
mation in an EIS, we must further keep in mind that agencies
are charged with "concentrat[ing] on the issues that are truly
significant to the action in question, rather than amassing
needless detail." 40 C.F.R. § 1500.1(b); see also id. § 1502.2
("[EISs] shall be analytic rather than encyclopedic."). That is
in part because an EIS containing vast quantities of inconse-
quential information can actually defeat the NEPA’s goals of
informed decisionmaking and public participation by drown-
ing out truly significant information with that which is insig-
nificant. Agencies therefore face a delicate balancing act: they
must include enough details about a proposed action to allow
for the requisite hard look at its environmental effects without
providing so much information that the EIS becomes self-
  3
   We have framed this argument as we understand it. It is unclear to us
whether Appellants believe that details regarding the construction and
operation of Site 16’s dam—such as the number of workers necessary for
construction, the size and location of the site, and the type of construction
equipment that will be used—also constitute connected actions. If so, we
agree with the district court that these aspects concerning the construction
and operation of Site 16’s dam do not constitute connected actions.
18                    WEBSTER v. USDA
defeating. Except when prescribed by statute or regulations,
deciding what details need to be included or omitted in an EIS
is generally a matter left to the agency’s discretion, which we
will not disturb unless we are convinced that its exercise pre-
vented the agency from taking a hard look at the action’s
environmental effects or the public from participating in the
decisionmaking process.

   Turning to the information Appellants insist was missing,
we note initially that the 2009 SEIS included at least some of
it. For example, whereas Appellants contend that the 2009
SEIS omitted information regarding the excavation of borrow
material for use in constructing the dam, it in fact discussed
where the borrow areas would be and provided a map show-
ing their locations. And, similarly, notwithstanding Appel-
lants’ assertion that the 2009 SEIS did not provide the size
and location of the construction site, it actually did describe
the size of the site and its location and provided a project map
showing the same.

   To the extent the 2009 SEIS did not include the other infor-
mation specified by Appellants, we find the omissions to be
inconsequential. The purportedly missing information
includes such items as the "[n]umber of workers needed for
construction," the "[l]ocation and distance of access roads,"
the "[l]ocation and distance of utility rights-of-ways," the
"[t]ype of construction equipment that would be used and for
how long," and the "[l]ocation and size of parking areas."
Appellants simply list the types of missing information with-
out any explanation as to their significance or how their omis-
sion impedes the NEPA’s goals of informed decisionmaking
and public participation. And the consequentiality of their
omission is not readily apparent to us. Instead, they strike us
as either needless detail that would clutter the 2009 SEIS or
trivial deficiencies that invite flyspecking. In the end, the
omission of this information does not disturb our belief that
the NRCS took a hard look at the Site 16 dam’s environmen-
tal effects and that the public had adequate information to par-
                      WEBSTER v. USDA                       19
ticipate in the decisionmaking process. As a result, we will
not second-guess the agency’s decision to omit it.

                              2.

   We also find unmeritorious Appellants’ assertion that the
NRCS violated the NEPA by failing to consider as connected
actions the construction and operation of a water treatment
facility and water distribution system.

   Agencies must consider connected actions in the same EIS.
40 C.F.R. § 1508.25(a)(1). This requirement is intended to
prevent agencies from engaging in segmentation, which
involves "an attempt to circumvent [the] NEPA by breaking
up one project into smaller projects and not studying the over-
all impacts of the single overall project." Coal. on W. Valley
Nuclear Wastes v. Chu, 592 F.3d 306, 311 (2d Cir. 2009)
(quoting Stewart Park & Reserve Coal., Inc. v. Slater, 352
F.3d 545, 559 (2d Cir. 2003)) (internal quotation marks omit-
ted). Connected actions include those that (1) "[a]utomatically
trigger other actions which may require environmental impact
statements"; (2) "[c]annot or will not proceed unless other
actions are taken previously or simultaneously"; or (3) "[a]re
interdependent parts of a larger action and depend on the
larger action for their justification." § 1508.25(a)(1). Gener-
ally, in determining whether actions are connected so as to
require consideration in the same EIS, courts employ an "in-
dependent utility" test, which asks whether each project
would have taken place in the other’s absence. See, e.g., N.
Plains Res. Council, Inc. v. Surface Transp. Bd., 668 F.3d
1067, 1087 (9th Cir. 2011); Chu, 592 F.3d at 312; Wilderness
Workshop v. U.S. Bureau of Land Mgmt., 531 F.3d 1220,
1228-29 (10th Cir. 2008). If so, they have independent utility
and are not considered connected actions. N. Plains Res.
Council, 668 F.3d at 1087-88.

  Appellants have failed to point to a water treatment facility
or water distribution system connected to the construction of
20                    WEBSTER v. USDA
the dam at Site 16. Although Appellants do not specifically
argue that the HCPSD’s planned development of the
Baker/Mathias Water Distribution System is a connected
action, we nevertheless underscore that it is independent of
the NRCS’s proposed action here. The NRCS emphasized
when responding to comments in the 2009 SEIS that the
HCPSD would implement its system regardless of whether
the dam at Site 16 was constructed and, conversely, that the
NRCS would add water supply to the dam at Site 16 even if
the HCPSD abandoned its system. Given that the
Baker/Mathias Water Distribution System is independent of
the NRCS’s construction of Site 16’s dam, it is not a con-
nected action.

   Furthermore, Appellants have failed to demonstrate that
any other water treatment facility or water distribution system
has been planned, much less in connection with the dam at
Site 16. Appellants apparently argue that because the Site 16
dam will include a water supply source, it will necessarily
require such a facility and system in the future to service the
source, so the NRCS should have considered them as con-
nected actions. Appellees, however, insist that there are no
plans for such a facility or system, and Appellants give us no
reason to question this representation. In the absence of any
impending plans to construct such a system or facility, seg-
mentation is not a concern. See Wilderness Workshop, 531
F.3d at 1229; O’Reilly v. U.S. Army Corps of Eng’rs, 477
F.3d 225, 236-37 (5th Cir. 2007). And, furthermore, we fail
to see how the agency could consider a water treatment facil-
ity and water distribution system, much less their impacts,
when there are no current plans to build them. Because such
a project is speculative at best and any discussion of its
impacts would be speculative, the agency was not required to
discuss it as a connected action. See Wyoming, 661 F.3d at
1253 ("In general, we have not required agencies to consider
‘speculative’ impacts or actions in an EIS . . . .").
                       WEBSTER v. USDA                         21
                               D.

   Appellants next maintain that the NRCS failed to consider
all reasonable alternatives in its 2009 SEIS.

   At the heart of an EIS is the required analysis of "alterna-
tives to the proposed action." 42 U.S.C. § 4332(C)(iii); 40
C.F.R. § 1502.14. In this section, the agency must
"[r]igorously explore and objectively evaluate all reasonable
alternatives." 40 C.F.R. § 1502.14(a). For alternatives that are
unreasonable, the agency need only briefly discuss its reasons
for eliminating them from detailed study. See id. Hence,
because alternatives that do not accomplish the purpose or
objective of the action are unreasonable, they require only a
brief explanation for their rejection. Wyoming, 661 F.3d at
1244. Also, the agency is not required "to analyze the envi-
ronmental consequences of alternatives it has in good faith
rejected as too remote, speculative, or . . . impractical or inef-
fective." Id. (omission in original) (quoting Citizens’ Comm.
to Save Our Canyons, 297 F.3d at 1030) (internal quotation
marks omitted) The agency, however, must always consider
"the alternative of no action." 40 C.F.R. § 1502.14(d).

   We are confident that the NRCS considered all reasonable
alternatives. Throughout the Project’s history, from the 1974
EIS and the various supplements and reports that followed it
to the 2009 SEIS, the NRCS studied numerous alternatives to
its proposed action. In the 2009 SEIS specifically, the NRCS
discussed seventeen alternatives. It offered appropriate rea-
sons for eliminating all but two from detailed study, includ-
ing, among other considerations, reasons related to technical
feasibility, pecuniary costs, and effectiveness in achieving the
purposes of the action. The NRCS then provided detailed
examination of the no-action alternative and the alternative
involving construction of the dam at Site 16. On its face, this
discussion of alternatives complies with the mandates of the
NEPA.
22                     WEBSTER v. USDA
   Appellants argue that the NRCS’s analysis is nevertheless
deficient because it failed to give detailed study to two gen-
eral types of alternatives. First, they maintain that the NRCS
should have afforded detailed consideration to alternatives
involving multiple actions that separately could achieve the
individual purposes underlying the dam at Site 16 . In fact, in
the 2009 SEIS, the NRCS considered alternatives that would
provide flood control and water supply separately, but elimi-
nated them from detailed consideration for various appropri-
ate reasons described above. Notably, Appellants fail to offer
a specific alternative involving multiple actions that the
NRCS should have considered in detail. Nor do they highlight
a specific alternative that the NRCS eliminated from further
consideration of which it should have provided detailed study.
So we are left only to speculate that one might exist, which
is an insufficient ground for disturbing the agency’s decision.
We therefore are unconvinced that the NRCS improperly
eliminated from detailed consideration alternatives involving
multiple actions that could achieve Site 16’s dam’s purposes
individually.

   Second, Appellants contend that the NRCS failed to con-
sider alternatives involving other sites for the proposed dam
within the Lost River Subwatershed. Instead, according to
Appellants, the NRCS simply relied upon the 1974 EIS’s con-
sideration of thirty other locations, even though the purposes
for the dam have changed. But that is inaccurate. In the 2009
SEIS, after noting that it examined thirty other locations lead-
ing up to the 1974 EIS, the NRCS asserted that as part of its
supplemental evaluation it had reconsidered whether the Site
16 and Site 23 locations were still the most viable alterna-
tives. It observed that its reevaluation prompted it to eliminate
Site 23 as infeasible. With respect to the dam at Site 16, it
determined that there were no new locations for impound-
ments that were viable and that would achieve the identified
purposes and needs. Appellants do not offer a location that
would call into question this determination, so we defer to it.
                          WEBSTER v. USDA                              23
The NRCS thus was not required to give this alternative
detailed consideration.

                                   E.

   Appellants assert that in the 2009 SEIS the NRCS failed to
address all of the environmental effects that would result from
construction of the dam at Site 16.4 In support, they list spe-
cific effects that they allege the NRCS neglected to consider.
Relatedly, according to Appellants, the NRCS also did not
conduct a sufficient cumulative-impacts analysis.

   An EIS must include a discussion of "the environmental
impact of the proposed action" and "any adverse environmen-
tal effects which cannot be avoided should the proposal be
implemented." 42 U.S.C. § 4332(C)(i)-(ii). Because "[t]his
section forms the scientific and analytic basis for the compari-
son[ ]" of alternatives, it must "include the environmental
impacts of the alternatives[,] including the proposed action."
40 C.F.R. § 1502.16.

   The CEQ has instructed agencies on the types of impacts
or "effects" (the regulations treat these terms as synonymous)
that they must consider: "ecological (such as the effects on
natural resources and on the components, structures, and func-
tioning of affected ecosystems), aesthetic, historic, cultural,
economic, social, or health." Id. § 1508.8. Agencies must
  4
    In addressing this issue, Appellants begin by insisting that the 2009
SEIS is deficient because it incorporated and relied on information set
forth in the 1974 EIS without indicating that the NRCS updated it or oth-
erwise ensured its continued accuracy. But given that the CEQ’s regula-
tions encourage agencies to tier their analyses and incorporate such prior
statements in subsequent statements by reference, see 40 C.F.R.
§ 1502.20, it was appropriate for the NRCS to rely on the 1974 EIS in its
2009 SEIS. Moreover, Appellants fail to highlight any inaccurate or out-
dated information upon which the NRCS relied. In the absence of evi-
dence that the NRCS relied on inaccurate or outdated information from the
1974 EIS, we will not assume that it did.
24                    WEBSTER v. USDA
study these effects whether they are direct, meaning that they
"are caused by the action and occur at the same time and
place," or indirect, which means that they "are caused by the
action and are later in time or farther removed in distance, but
are still reasonably foreseeable." Id. Additionally, agencies
have to examine cumulative impacts resulting from "the
incremental impact of the [proposed] action when added to
other past, present, and reasonably foreseeable future
actions." Id. § 1508.7. Yet although agencies must take into
account effects that are reasonably foreseeable, they generally
need not do so with effects that are merely speculative. Wyo-
ming, 661 F.3d at 1253.

   After reviewing the 2009 SEIS, we are convinced that the
NRCS took a hard look at the environmental effects that con-
struction of the dam at Site 16 would have. The 2009 SEIS
provided detailed analyses of the dam’s effects on the follow-
ing: flood damage; public health and safety; water supply,
including its economic implications; soil erosion and sedi-
mentation; agricultural productivity; prime and unique farm-
land; land use and upland habitats; aquatic resources;
recreation; riparian areas; wetlands; waters of the United
States; water quality; threatened and endangered species;
invasive species; historic, scientific, and cultural resources;
and environmental justice. The NRCS examined the effects of
each with relation to both the no-action alternative and the
construction of the dam.

   The 2009 SEIS also contained a cumulative-impacts analy-
sis in which it discussed the environmental effects that con-
struction of the dam at Site 16 would have in conjunction with
the effects of five other projects in the area. Contrary to
Appellants’ assertion, the NRCS considered the overall cumu-
lative impact of these projects with respect to various environ-
mental effects, including, but not limited to, effects on
forestland, farmland, wetlands, and habitats. In the end, we
are satisfied that the NRCS performed a thorough investiga-
                      WEBSTER v. USDA                       25
tion into the action’s effects and candidly acknowledged its
risks.

   Our opinion that the NRCS took a hard look at the environ-
mental effects of constructing the dam at Site 16 is undis-
turbed by the specific effects that Appellants contend the
NRCS failed to discuss. It is again clear that the NRCS con-
sidered at least one of the sources of information that Appel-
lants insist is missing—specifically, the impact that the dam
would have on downstream fisheries. The NRCS, in its dis-
cussion of the Site 16 dam’s effects on aquatic resources, can-
didly acknowledged that the dam "would result in a barrier to
fish movement between the upper reaches of Lower Cove
Run and the lower sections of this stream and the main stem
[of the] Lost River."

   Other effects that Appellants maintain are missing are
either speculative or relatively inconsequential flyspecks. For
instance, similar to their argument regarding connected
actions, Appellants assert that the NRCS should have consid-
ered the effects resulting from the construction of a new water
treatment facility and water distribution system to service the
water supply source at Site 16’s dam. But, as we explained,
such a system has not been planned and is speculative, mak-
ing any effects resulting from it speculative as well. After
reviewing the remainder of Appellants’ list of purportedly
unaddressed effects and considering the 2009 SEIS’s discus-
sion of environmental effects holistically, we remain con-
vinced that the NRCS took a hard look at the action’s
environmental effects.

                              F.

   Appellants assert that the NRCS included a misleading and
inaccurate cost-benefit analysis. They highlight the following
as contributing to its misleading nature: 1) the NRCS admit-
ted that the usual design life for watershed-protection and
flood-prevention structures is fifty to one hundred years, but
26                     WEBSTER v. USDA
in its cost-benefit analysis, it used a design life of one hundred
years, the far end of the spectrum; 2) the NRCS’s cost-benefit
ratio compared the costs and benefits of the Project as a
whole, not Site 16 specifically, which, according to Appel-
lants, may mask a less desirable cost-benefit ratio for Site 16
alone; and 3) the NRCS included as benefits over $900,000
that would result from incidental recreation, even though it
eliminated recreation as a purpose.

   We have emphasized before that an agency must weigh a
proposed action’s benefits with its environmental costs. See
Ohio Valley Envtl. Coal., 556 F.3d at 191 ("[E]ven agency
action with adverse environmental effects can be NEPA-
compliant so long as the agency has considered those effects
and determined that competing policy values outweigh those
costs."); Hughes River Watershed Conservancy v. Johnson,
165 F.3d 283, 289 (4th Cir. 1999) ("NEPA requires agencies
to balance a project’s economic benefits against that project’s
environmental effects."). The CEQ’s regulations require that
an EIS "at least indicate those considerations, including fac-
tors not related to environmental quality, which are likely to
be relevant and important to a decision." 40 C.F.R. § 1502.23.
Along these lines, an EIS should provide enough detail con-
cerning the drawbacks and merits of the proposed action to
allow for reasoned evaluation and decisionmaking. See Subur-
ban O’Hare Comm’n v. Dole, 787 F.2d 186, 191 n.8 (7th Cir.
1986).

   But an agency need not include a cost-benefit analysis in an
EIS when comparing the different alternatives. See § 1502.23.
That said, if an agency considers "a cost-benefit analysis rele-
vant to the choice among environmentally different alterna-
tives," it must either append it to the EIS or incorporate it by
reference. Id. The agency does not, however, need to display
the weighing of the merits and drawbacks of the alternatives
in a monetary cost-benefit analysis. Id. And indeed it would
be improper to do so "when there are important qualitative
considerations." Id.
                       WEBSTER v. USDA                        27
   In any event, an EIS may be deficient if its assessment of
the costs and benefits of a proposed action relies upon "mis-
leading economic assumptions." Hughes River Watershed
Conservancy v. Glickman, 81 F.3d 437, 446 (4th Cir. 1996).
Misleading economic assumptions can prevent the agency
from engaging in informed decisionmaking when balancing
the proposed action’s benefits with its environmental effects.
Id. They can also preclude meaningful public participation
"by skewing the public’s evaluation of" the action. Id. We
remain cognizant, however, that the weighing of a project’s
benefits with its costs lies at the core of an agency’s discre-
tion, so we perform "a ‘narrowly focused’ review of the eco-
nomic assumptions underlying a project to determine whether
[they] ‘were so distorted as to impair fair consideration’ of the
project’s adverse environmental effects." Id. (quoting S. La.
Envtl. Council, Inc. v. Sand, 629 F.2d 1005, 1011 (5th Cir.
1980)).

  Here, the NRCS included a comparison of the monetary
and qualitative costs and benefits of the two alternatives it
analyzed in detail—the dam at Site 16 and the no-action alter-
native. Contrary to Appellants’ assertions, the analysis is not
misleading and does not thwart the NEPA’s goals of informed
decisionmaking and public participation. First, there is noth-
ing misleading or problematic about the fact that the NRCS
used a project life of one hundred years for Site 16’s dam,
particularly when that period is within the usual range for
such projects, even if it as at the high end of the normal range.
Using a project life of one hundred years was a reasonable
exercise of the agency’s discretion.

   Second, there is no danger that the NRCS sought to mask
the relative costs and benefits of Site 16 alone by focusing on
the Project as a whole. Incorporated in the 2009 SEIS was a
chart comparing the costs and benefits of the Project if Site
16’s dam is constructed with the costs and benefits of the
Project if Site 16’s dam is not constructed. It includes a com-
parison of both monetary and nonmonetary benefits and costs.
28                    WEBSTER v. USDA
This comparison brings into relief the relative costs and bene-
fits specific to Site 16. Regardless of whether the cost-benefit
ratio focused on the Project as a whole, it is evident that the
NRCS considered the costs and benefits of Site 16 specifi-
cally, and that the public had the information to do the same.

   Finally, it was not misleading for the NRCS to include inci-
dental recreational benefits after removing recreation as a pur-
pose. The 2009 SEIS explained that, although recreation was
no longer a purpose for the dam at Site 16, incidental recre-
ation, such as fishing, bird watching, boating, and hiking,
would still occur. The estimated benefits reflected this inci-
dental recreation, and nothing suggests that this amount is
inflated or otherwise erroneous.

                              G.

   Appellants contend that the 2009 SEIS failed to provide
sufficient detail about planned mitigation measures so that
they could be fairly evaluated. According to Appellants, the
2009 SEIS includes only unspecified measures. As proof, they
point to the NRCS’s response to a comment in the 2009 SEIS
in which it stated that in the future, to obtain the necessary
Clean Water Act Section 404 permit from the Army Corps of
Engineers and Section 401 state water quality certification, it
would develop a compensatory mitigation plan further
addressing wetlands impacts.

   An "important ingredient of an EIS is the discussion of
steps that can be taken to mitigate adverse environmental con-
sequences." Robertson, 490 U.S. at 351. The statutory man-
date that agencies detail "any adverse environmental effects
which cannot be avoided should the proposal be imple-
mented," 42 U.S.C. § 4332(C)(ii), implicitly assumes "that the
EIS will discuss the extent to which adverse effects can be
avoided," Robertson, 490 U.S. at 352. The CEQ’s regulations
impose such a requirement more explicitly. In scattered provi-
sions, they instruct agencies to "discuss possible mitigation
                      WEBSTER v. USDA                        29
measures in defining the scope of the EIS, in discussing alter-
natives to the proposed action and consequences of that
action, and in explaining its ultimate decision." Id. (citations
omitted) (citing 40 C.F.R. §§ 1502.14(f), 1502.16(h),
1505.2(c), 1508.25(b)).

   To satisfy these procedural mandates, an EIS must contain
a "reasonably complete discussion of possible mitigation mea-
sures," which requires an examination of mitigation measures
"in sufficient detail to ensure that environmental conse-
quences have been fairly evaluated." Id. This ordinarily obli-
gates agencies to do more than simply list possible mitigation
measures. San Juan Citizens Alliance v. Stiles, 654 F.3d 1038,
1053-54 (10th Cir. 2011). But there is no "substantive require-
ment that a complete mitigation plan be actually formulated
and adopted." Robertson, 490 U.S. at 352. The inquiry into
the level of specificity required to provide a reasonably com-
plete mitigation discussion is necessarily contextual. See
Stiles, 654 F.3d at 1054. An EIS for a "large-scale, multi-step
project" will generally demand less detail than an EIS for a
"relatively contained, site-specific proposal." Id.

   As a statement pertaining to a site-specific proposal, the
2009 SEIS contained a reasonably complete discussion of
possible mitigation measures. It did not simply list possible
measures. Instead, after describing the dam at Site 16 as the
recommended alternative for achieving its purposes, the
NRCS provided a "Mitigation Summary" in which it first
identified environmental effects that construction of the dam
at Site 16 would have and then explained measures it would
take to mitigate each effect. Notwithstanding Appellants
claim to the contrary, these measures, by and large, intro-
duced specific proposals to alleviate specific effects. An
example involves the NRCS’s discussion of measures it
would take to mitigate the action’s effects on wetlands. The
NRCS provided a map with wetland areas marked on it and,
using that map, described how it would attempt to avoid cer-
30                    WEBSTER v. USDA
tain marked areas. It also described planned efforts to create
new wetlands in specified locations.

   Moreover, the Mitigation Summary was not the only sec-
tion of the 2009 SEIS that discussed mitigation measures.
When explaining the environmental effects of the alternatives,
the 2009 SEIS described specific mitigation measures the
NRCS would take to alleviate the Site 16 dam’s effects. For
instance, after reporting how the permanent lake created by
the dam at Site 16 could cause increased water temperatures,
it stated that "[t]o avoid adverse temperature impacts to the
fishery downstream of Site 16, a cold water release in the
principal spillway structure will be included with the riser
configuration." Such discussions of specific, detailed mitiga-
tion measures that are responsive to specified effects reinforce
our belief that the NRCS fairly evaluated the action’s environ-
mental consequences.

   The NRCS’s allusion to the fact that to obtain required per-
mits it would have to develop a compensatory mitigation plan
related to wetlands effects does not dissuade us of this belief.
Again, there is no requirement that the agency formulate and
adopt a complete mitigation plan at this stage. See Robertson,
490 U.S. at 352-53. That the NRCS may have to develop fur-
ther mitigation measures in the future to comply with permit
requirements does not render its current mitigation discussion
insufficient under the NEPA. In the 2009 SEIS, the NRCS
provided a detailed discussion of various mitigation measures
it would take to reduce wetlands effects. It is enough, for pur-
poses of the NEPA, to demonstrate that the NRCS took a hard
look at the effects its action would have on wetlands and that
it developed plans to mitigate those effects.

                              H.

  Appellants lastly contend that the NRCS violated the
NEPA by failing to invite the Army Corps of Engineers to
participate in preparing the 2009 SEIS as a cooperating
                      WEBSTER v. USDA                        31
agency despite learning that it needed to obtain a Clean Water
Act Section 404 permit from the Army Corps.

   Lead agencies must request that agencies having "jurisdic-
tion by law" participate in the NEPA process as cooperating
agencies. 40 C.F.R. § 1501.6. Agencies have jurisdiction by
law if they possess "authority to approve, veto, or finance all
or part of the proposal." Id. § 1508.15. Once requested, coop-
erating agencies are required to participate in the NEPA pro-
cess. Id. § 1501.6(b)(1).

   Even assuming that the NRCS did not ask the Army Corps
to participate as a cooperating agency and that it should have
done so, such error was harmless. See United States v. Coal.
for Buzzards Bay, 644 F.3d 26, 37 (1st Cir. 2011) (recogniz-
ing that harmless-error review applies to violations of the
NEPA). Despite bearing the burden to establish harm, see id.,
Appellants fail to show, or even suggest, any harm that
resulted from the failure to designate the Army Corps as a
cooperating agency. Nor do we identify any harm resulting
from this failure. In fact, the record reflects that the NRCS
provided the Army Corps opportunities to participate in pre-
paring both the 2007 SEIS and the 2009 SEIS, and that the
Army Corps took advantage of at least some of these opportu-
nities. It not only provided a letter in October 2006 comment-
ing on the draft leading to the 2007 SEIS, but it also
participated in a wetlands delineation and conference calls
and meetings regarding Site 16 prior to the issuance of the
2009 SEIS. It is evident that the Army Corps provided input
that assisted the NRCS’s preparation of the 2009 SEIS.

   Alternatively, Appellants argue that the NRCS should not
have issued the 2009 SEIS prior to receiving the Clean Water
Act Section 404 permit from the Army Corps. But we are
aware of no requirement that the NRCS obtain necessary per-
mits before issuing an EIS. To the contrary, the CEQ’s regula-
tions mandate only that it list all necessary federal permits in
a draft EIS. See 40 C.F.R. § 1502.25(b). Thus, the NRCS’s
32                   WEBSTER v. USDA
issuance of the 2009 SEIS before obtaining the requisite per-
mit from the Army Corps does not violate the NEPA.

                            IV.

  For these reasons, we affirm the decision of the district
court.

                                                AFFIRMED
