                  FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

SISKIYOU REGIONAL EDUCATION            
PROJECT,
               Plaintiff-Appellant,
                v.                          No. 06-35332
UNITED STATES FOREST SERVICE;                D.C. No.
                                           CV-03-03013-JPC
SCOTT CONROY, Forest Supervisor
Siskiyou National Forest; LISA
BARTON; ROBERT BARTON; GERALD
HOBBS,
             Defendants-Appellees.
                                       

SISKIYOU REGIONAL EDUCATION            
PROJECT,
                 Plaintiff-Appellee,
                v.
UNITED STATES FOREST SERVICE;
SCOTT CONROY, Forest Supervisor             No. 06-35373
Siskiyou National Forest; GERALD
HOBBS,                                       D.C. No.
                                           CV-03-03013-HO
                       Defendants,
               and
LISA BARTON; ROBERT BARTON;
LISA BARTON; ROBERT BARTON,
WALDO MINING DISTRICT,
           Defendants-Appellants.
                                       


                            5337
5338         SISKIYOU REGIONAL EDUCATION v. USFS



SISKIYOU REGIONAL EDUCATION            
PROJECT,
                 Plaintiff-Appellee,
                v.
UNITED STATES FOREST SERVICE;
SCOTT CONROY, Forest Supervisor             No. 06-35381

                                       
Siskiyou National Forest; LISA                D.C. No.
BARTON; ROBERT BARTON,                     CV-03-03013-JPC
                       Defendants,
                                              OPINION
WALDO MINING DISTRICT,
                         Defendant,
               and
GERALD HOBBS,
              Defendant-Appellant.
                                       
         Appeal from the United States District Court
                  for the District of Oregon
         Michael R. Hogan, District Judge, Presiding

                   Argued and Submitted
             February 7, 2008—Portland, Oregon

                     Filed May 7, 2009

       Before: Pamela Ann Rymer, Thomas G. Nelson and
                Richard A. Paez, Circuit Judges.

                   Opinion by Judge Paez
5342        SISKIYOU REGIONAL EDUCATION v. USFS
                         COUNSEL

Peter M.K. Frost, Western Environmental Law Center,
Eugene, Oregon; Roger Flynn, Jeffrey C. Parsons, Western
Mining Action Project, Lyons, Colorado, for plaintiff-
appellant Siskiyou Regional Education Project.

Sue Ellen Woolridge, Lane M. McFadden, Lisa Jones, Brian
C. Toth, attorneys, Enviromental & Natural Resources Divi-
sion, Department of Justice, Washington, D.C., for defendant-
appellee United States Forest Service.

James L. Buchal, Murphy & Buchal LLP, Portland, Oregon,
for Robert Barton.

David Young, Law Offices of David Young, Los Angeles,
California; Christopher L. Cauble, Cauble, Dole & Sorenson,
Grants Pass, Oregon, for Gerald Hobbs.


                         OPINION

PAEZ, Circuit Judge:

  Siskiyou Regional Education Project (“SREP”) and interve-
nor miners Robert Barton (“Barton”) and Gerald Hobbs
(“Hobbs”) appeal the district court’s rulings in favor of the
United States Forest Service (“Forest Service”) on claims
brought in connection with the Forest Service’s interpretation
of Mineral Management Standard and Guideline MM-1
(“MM-1”), a mining-related directive contained in the Forest
Service’s Northwest Forest Plan (“NFP”).

   The NFP provides that Standards and Guidelines do not
apply when contrary to existing law or regulation. Although
36 C.F.R. § 228.4(a) (2002), a Forest Service mining regula-
tion, was in force when MM-1 was adopted, MM-1 and
               SISKIYOU REGIONAL EDUCATION v. USFS                    5343
§ 228.4(a) conflict in the extent of regulatory oversight of
small mining operations in riparian reserves. Specifically,
§ 228.4(a) confers discretionary authority on district rangers
to determine whether mining activity will result in significant
disturbance to surface resources and therefore require a plan
of operations. MM-1 appears to conflict with § 228.4(a)
because it directs the district ranger to require a plan of opera-
tions for all mining activity within riparian reserves. To
resolve this apparent conflict, in February 2002 the Forest
Service interpreted MM-1 to impose the same threshold stan-
dard for a plan of operations as § 228.4(a). The Forest Ser-
vice’s interpretation of MM-1 lies at the heart of this dispute.

    The district court rejected SREP’s challenge to the Forest
Service’s interpretation of MM-1, and granted summary judg-
ment to the Forest Service. The district court also limited
intervention by Barton and Hobbs to the remedial phase of the
litigation, if necessary. The court dismissed as moot Barton’s
separate action that had been consolidated with SREP’s suit.
The court also struck Hobbs’s Answer to SREP’s First
Amended Complaint on the ground that it raised claims that
exceeded Hobbs’s limited role in the litigation.

   On appeal, SREP challenges the district court’s grant of
summary judgment in favor of the Forest Service. SREP
maintains that the Forest Service’s interpretation of MM-1 as
“contrary to” § 228.4(a), and thus without force insofar as it
imposes additional restrictions on mining activity in riparian
reserves, was arbitrary and capricious. Barton appeals the dis-
trict court’s denial of his motion to intervene at the merits
phase of SREP’s suit against the Forest Service, which would
have permitted him to assert that the Forest Service lacks the
authority to regulate mining under the NFMA. He also chal-
lenges dismissal of his separate action as moot. Barton argues
that because the National Forest Management Act of 1976
(“NFMA”) does not grant the Forest Service authority to reg-
ulate mining, its attempt to do so in the NFP is unenforceable.1
  1
   That is, although Barton agrees with the Forest Service, that MM-1
should not be construed to limit mining in riparian reserves, his contention
5344             SISKIYOU REGIONAL EDUCATION v. USFS
Barton further argues that even if the Forest Service is vested
with this authority, its interpretation of MM-1 was reasonable
and entitled to deference. Last, Hobbs argues that the counter-
claims and affirmative defenses he raised in his Answer to
SREP’s First Amended Complaint were improperly stricken.

   At the outset, we conclude that, contrary to the Forest Ser-
vice’s objections, we have jurisdiction over final agency
action pursuant to 28 U.S.C. § 1291. We affirm both the dis-
trict court’s grant of summary judgment in favor of the Forest
Service, and the court’s rulings regarding Barton and Hobbs.

            I.    FACTUAL AND PROCEDURAL HISTORY

  Streams and Mining in the Siskiyou National Forest

   The Siskiyou National Forest contains streams and rivers
that provide habitat for several fish species, including coho
and chinook salmon and steelhead trout. Several of these spe-
cies, including coho salmon, have been listed as threatened or

is broader in scope: he argues that the Forest Service lacks authority to
regulate mining under NFMA at all. Because we ultimately conclude that
Barton’s claims are moot, we need not directly address his contention that
the Forest Service lacks the authority to regulate mining under the NFMA.
We note, however, that the Supreme Court, and at least one of our sister
circuits, have acknowledged this authority. See Cal. Coastal Comm’n v.
Granite Rock Co., 480 U.S. 572, 585 (1987) (“[U]nder the National Forest
Management Act . . . the Forest Service under the Secretary of Agriculture
is responsible for the management of the surface impacts of mining on
federal forest lands.”) (citation omitted)); Park Lake Res. LLC v. USDA,
197 F.3d 448, 451 (10th Cir. 1999) (listing a provision of the NFMA as
one of the many “statutory and regulatory provisions governing national
forests upon which it might rely” in requiring modifications to a mining
plan of operations). Although SREP contends that the Court’s statement
in Coastal Commission should be ignored as dicta, we “do not treat con-
sidered dicta of the Supreme Court lightly.” United States v. Choudhry,
461 F.3d 1097, 1102 n.4 (9th Cir. 2006) (citing United States v. Montero-
Camargo, 208 F.3d 1122, 1132 n.17 (9th Cir. 2000)).
              SISKIYOU REGIONAL EDUCATION v. USFS                  5345
at risk under the Endangered Species Act. See, e.g., 70 Fed.
Reg. 37160, 3170-71 (June 28, 2005). Many of these same
waterways have also been subject to gold mining claims since
the mid-1800s. Currently, gold miners work the streams and
rivers within the forest with “suction dredges,” machines that
separate gold from streambed material using a gasoline-
powered motor that draws streambed material up through a
flexible, two-to-four-inch intake hose and then discharges the
material back into the stream bed. The co-existence of pro-
tected fish species and mining operations in streams and riv-
ers raises concern because suction dredges are a popular
method of mining the waterways within the forest, yet may
cause harm to endangered fish.2

  Regulatory History

   A complex, interlocking web of statutes and regulations
sets forth the Forest Service’s authority to regulate mining
operations in the streams and rivers within the Siskiyou
National Forest. Historically, mining operations on public
lands were subject to little regulation. See generally Laura S.
Ziemer, The 1872 Mining Law and the 20th Century Collide:
A Rediscovery of Limits on Mining Rights in Wilderness
Areas and National Forests, 28 Envt’l L. 145, 146-47 (1998).
The General Mining Act of 1872 (codified as amended in
scattered sections of 30 U.S.C.), and the National Park Ser-
vice Organic Act of 1897 (“Organic Act”) (codified as
amended in scattered sections of 16 U.S.C.) granted the Forest
Service the authority to promulgate regulations for mining in
national forests. See United States v. Shumway, 199 F.3d
1093, 1106-07 (9th Cir. 1999) (quoting 16 U.S.C. §§ 478 and
551). Pursuant to its authority under the Organic Act, the
  2
    SREP contends that suction dredge mining is harmful to endangered
fish. We note that, although this contention provides background informa-
tion helpful to understanding the basis for SREP’s lawsuit, the question
whether suction dredge mining is harmful to fish is not before us and,
accordingly, we do not address it.
5346           SISKIYOU REGIONAL EDUCATION v. USFS
Forest Service first adopted mining regulations in 1974. See
39 Fed. Reg. 31317 (Aug. 28, 1974). When the Forest Service
issued its February 2002 interpretation of MM-1 that SREP
challenges here, 36 C.F.R. § 228.4(a) (2002)3 provided in per-
tinent part:

      (a)   Except as provided in paragraph (a)(2) of this
            section, a notice of intention to operate is
            required from any person proposing to conduct
            operations which might cause disturbance of
            surface resources. Such notice of intention shall
            be submitted to the District Ranger having
            jurisdiction over the area in which the opera-
            tions will be conducted. If the District Ranger
            determines that such operations will likely
            cause significant disturbance of surface
            resources, the operator shall submit a proposed
            plan of operations to the District Ranger.4

36 C.F.R. § 228.4(a) (2002); see 36 C.F.R. § 228.4(a)(4)
(2005). Although this regulation requires a notice of intent in
certain circumstances, it vests discretion in the district ranger
to determine if the mining operation “will likely cause signifi-
cant disturbance of surface resources.” Id. In the event of such
  3
     Since the Forest Service’s February 2002 interpretation of MM-1, the
Forest Service has promulgated revised regulations related to mining
within the national forests. See 69 Fed. Reg. 41428 (July 9, 2004); 70 Fed.
Reg. 32731 (June 6, 2005). The revised regulations retain the basic
requirements of the earlier version, and do not materially affect suction-
dredge mining. We continue to refer to the version of § 228.4 that was
in force when the February 2002 interpretation issued, unless otherwise
noted.
   4
     A notice of intent need only contain information “sufficient to identify
the area involved, the nature of the proposed operations, the route of
access to the area of operations and the method of transport.” 36 C.F.R.
§ 228.4(a)(2)(iii). In contrast, a plan of operations requires more detailed
information, including “the approximate location and size of areas where
surface resources will be disturbed” and “measures to be taken to meet the
requirements for environmental protection.” Id. at § 228.4(c).
             SISKIYOU REGIONAL EDUCATION v. USFS           5347
a determination, the mining operator must submit a proposed
plan of operations.

   Section 228.4(a) contained five exceptions to the plan of
operations requirement, including an exception for individuals
desiring to search for and occasionally remove small mineral
samples or specimens, and an exception for prospecting and
sampling that does not cause significant surface resource dis-
turbance or involve removal of more than a reasonable
amount of mineral deposit for analysis and study. Id. at
§ 228.4(a)(1)(i)-(iv). Further, § 228.4(a) provided that “[a]
notice of intent need not be filed: (i) Where a plan of opera-
tions is submitted for approval in lieu thereof, (ii) For opera-
tions excepted [by the provisions in § 228.4(a)(1)(i)-(v)],” and
in certain other circumstances. Id. at § 228.4(a)(2).

   Additionally, the NFMA requires the Forest Service to pre-
pare for each forest a management plan that contains stan-
dards and guidelines specifying how the forest shall be
managed. 16 U.S.C. §§ 1604(a), (e); Lands Council v. Powell,
395 F.3d 1019, 1032 (9th Cir. 2005) (“[The] NFMA requires
the Forest Service to create a comprehensive Forest Plan for
each national forest.” (citations omitted)). Pursuant to this
requirement, the Forest Service first adopted a plan for the
Siskiyou National Forest in 1989. That plan was amended in
1994, in response to President Clinton’s call for management
reform of federal lands and waters within the range of the
northern spotted owl. See Record of Decision for Amendments
to Forest Service and Bureau of Land Management Planning
Documents Within the Range of the Northern Spotted Owl,
Summary, April 13, 1994, available at http://www.reo.gov/
library/reports/newroda.pdf [hereinafter Record of Decision].

   The NFP contains an Aquatic Conservation Strategy
(“ACS”), the purpose of which is to protect fish habitat and
to maintain or restore riparian and aquatic ecosystems. Id. at
9. The ACS designates certain streams in the forest as riparian
reserves, portions of watersheds where riparian-dependent
5348         SISKIYOU REGIONAL EDUCATION v. USFS
resources receive primary emphasis. Id. at 7; see also Michael
C. Blumm, The Amphibious Salmon: The Evolution of
Ecosystem Management in the Columbia River Basin, 24
Ecology L. Q. 653, 669 (1997) (discussing policy and proce-
dures of ACS). To implement this strategy, the NFP contains
standards and guidelines that address matters such as timber
management, road construction, grazing, and restoration.
Record of Decision at 9.

   These “binding standards and guidelines . . . restrict certain
activities within areas designated as riparian reserves or key
watersheds.” Pacific Coast Fed’n of Fishermen’s Ass’n, Inc.,
v. Nat’l Marine Fisheries Serv., 265 F.3d 1028, 1032 (9th Cir.
2001); see 16 U.S.C. § 1604(i). By their own terms, however,
the Standards and Guidelines “do not apply where . . . con-
trary to existing law or regulation.” Standards and Guidelines
for Management of Habitat for Late-Successional and Old-
Growth Forest Related Species Within the Range of the
Northern Spotted Owl, at A-6 (April 13, 1994), available at
http:/www.reo.gov/library/reports/newsandga.pdf [hereinafter
Standards and Guidelines]; see also id. at C1.

  As noted above, the provision central to this dispute is
Standard and Guideline MM-1 (“MM-1”), which provides:

    Require a reclamation plan, approved Plan of Oper-
    ations, and reclamation bond for all minerals opera-
    tions that include Riparian Reserves. Such plans and
    bonds must address the costs of removing facilities,
    equipment, and materials; recontouring disturbed
    areas to near pre-mining topography; isolating and
    neutralizing or removing toxic or potentially toxic
    materials; salvage and replacement of topsoil; and
    seedbed preparation and revegetation to meet
    Aquatic Conservation Strategy objectives.

Standards and Guidelines at C-34 (emphasis added). Read in
isolation, MM-1 appears to require a plan of operation for all
               SISKIYOU REGIONAL EDUCATION v. USFS                      5349
mineral operations that include riparian reserves. Unlike
§ 228.4(a), which draws a distinction between mining opera-
tions that require only a notice of intent and those that require
a more comprehensive plan of operations, MM-1 draws no
such distinction for operations within riparian reserves.

  The Forest Service addressed the tension between MM-1
and § 228.4(a) in a memorandum that it issued on February 5,
2002:5
  5
    The Forest Service’s interpretation of MM-1 has shifted over time. In
1995, after the adoption of the NFP, SREP filed suit against the Forest
Service alleging that it violated the NFMA when it interpreted MM-1 to
allow small placer mining activity, such as suction dredge mining, in a
riparian reserve without requiring a plan of operations. See Nat’l Wildlife
Fed’n v. Agpaoa, CV 95-3005-CO (D. Or. Jan. 23, 1995). That case set-
tled when the Forest Service agreed to propose changes in management
direction for suction dredge mining in riparian reserves. As the Forest Ser-
vice explains, it then proposed an amendment to MM-1 in 1996 following
the preparation of an environment assessment (‘EA’) and a finding of no
significant impact. As amended, MM-1 would have required a plan of
operations for mining activity in riparian reserves only when the Forest
Service determined that such operations were “likely to significantly
retard or prevent attainment of the Aquatic Conservation Strategy” objec-
tives in the NFP. Siskiyou Reg’l Educ. Project v. Rose, 87 F. Supp. 2d
1074, 1081 (D. Or. 1999). However, because the Forest Service failed to
comply with certain procedural requirements of the National Environmen-
tal Policy Act (“NEPA”), the Rose court invalidated the proposed amend-
ment.
   After Rose, the Forest Service began to interpret MM-1 to require a plan
of operations for all mining activities in a riparian reserve. To that end, in
2001, the Forest Service, through initiation of a new NEPA process,
sought to establish a “programmatic” method for approving plans of oper-
ation for suction dredge mining under MM-1. Under this approach, so
long as a proposed plan of operations satisfied the programmatic criteria,
there would be no need to subject a proposed plan of operations to a full
NEPA review. Because the Forest Service never completed the NEPA
process, it never implemented a programmatic approval process for suc-
tion dredge mining in riparian reserves. In 2002, the Forest Service
adopted the interpretation of MM-1 that is at issue in this appeal.
5350        SISKIYOU REGIONAL EDUCATION v. USFS
    To apply [S&G MM-1] to activities not meeting the
    “likely cause significant disturbance” test is not
    appropriate, and is contrary to law and regulation. If
    no significant surface disturbance is occurring, we
    have no reason to require a reclamation bond, nor
    would we be able to determine bond amount. In the
    areas covered by the Northwest Forest Plan or cov-
    ered by other general management guidance or strat-
    egies, forest users can conduct non-significant
    surface disturbing activities without filing plans of
    operations per the intent of the Forest Service Min-
    ing Regulations. A Notice of Intent to Operate (NOI)
    will still be required if the proposed activity might
    cause disturbance of surface resources and it doesn’t
    meet the provisions of 36 CFR 228.4(a)(2). The
    MM-1 standard and guideline applies only when the
    proposed activity is likely to cause significant sur-
    face disturbance. Because MM-1 would require
    plans of operations where [§] 228[.4(a)] would not,
    it was contrary to existing regulation insofar as it
    was interpreted to include plans of operation for all
    suction-dredge mining.

Memorandum to Regional Foresters (February 5, 2002). After
the Forest Service issued this management directive, the For-
est Service began to allow miners to undertake suction-dredge
mining operations in riparian reserves within the Siskiyou
National Forest upon the filing of a notice of intent, without
requiring the submission or approval of a plan of operations.
Barton’s and Hobbs’s mining operations were among those
that were allowed to proceed without an approved plan of
operations.

  Procedural History

   In 2003, SREP filed suit, alleging that the Forest Service’s
February 2002 interpretation of MM-1 violated the NFP and
the NFMA, and, therefore, its decision to allow suction
               SISKIYOU REGIONAL EDUCATION v. USFS                  5351
dredge mining operations in riparian reserves without a plan
of operations was arbitrary and capricious under the Adminis-
trative Procedure Act (“APA”), 5 U.S.C. § 551 et seq.6
Shortly after SREP filed suit, Hobbs, Barton and the Waldo
Mining District (“WMD”) moved separately to intervene. The
district court granted intervention to Barton and Hobbs only
as to the remedial phase of the litigation. Barton and WMD
then filed a separate suit against the Forest Service, which the
district court consolidated with SREP’s suit.7

   All parties filed cross-motions for summary judgment. In
Barton’s suit against the Forest Service, the district court
granted summary judgment in favor of the Forest Service. The
court concluded that Barton’s claims were moot in light of the
Forest Service’s policy decision to require a plan of opera-
tions under MM-1 only when the mining operation posed a
risk of significant surface disturbance. In SREP’s suit against
the Forest Service, the district court granted summary judg-
ment in favor of the Forest Service, concluding that MM-1
was “contrary to” § 228.4(a) and that the Forest Service’s nar-
row interpretation of MM-1 was reasonable and thus entitled
to deference. SREP, Barton and Hobbs timely appealed.

                         II.   JURISDICTION

      Final Agency Action

  [1] The Forest Service argues that we lack jurisdiction
because SREP’s complaint failed to challenge a final agency
action and constituted an improper programmatic attack on
  6
     SREP also alleged a claim under the Endangered Species Act, but that
claim was dismissed without prejudice and is not part of this appeal.
   7
     WMD was dismissed from the separate suit, and Barton was ordered
to file an amended complaint which does not contain any allegations relat-
ing to WMD. Although WMD was included in Barton’s notice of appeal,
WMD does not advance a challenge to its dismissal from the separate suit.
Therefore, any issues relating to WMD’s dismissal are deemed waived.
See Eng v. Cooley, 552 F.3d 1062, 1072 (9th Cir. 2009).
5352           SISKIYOU REGIONAL EDUCATION v. USFS
the Forest Service’s policies. The right of judicial review
under the APA is limited to “final agency action for which
there is no other adequate remedy in a court.” 5 U.S.C. § 704;
see Lujan v. Nat’l Wildlife Fed’n, 497 U.S. 871 (1990). A
“wholesale improvement” for a program cannot be sought by
“court decree, rather than in the offices of [the agency] or the
halls of Congress, where programmatic improvements are
normally made.” Norton v. S. Utah Wilderness Alliance, 542
U.S. 55, 64 (2004) (citing Lujan, 497 U.S. at 891). Rather,
“[u]nder the terms of the APA, respondent must direct its
attack against some particular ‘agency action’ that causes it
harm.” Id.

   SREP has expressed more than a generalized dissatisfaction
with the Forest Service’s decision to limit the application of
MM-1, even though SREP does not challenge the promulga-
tion of the NFP itself or the § 228.4(a) regulations. SREP’s
complaint refers to specific instances of suction dredge min-
ing operations that took place without an approved plan of
operations in waterways administered by the Forest Service.
The complaint further alleges that Barton and Hobbs “have
mined their claims, and intend to do so in the future . . . .
Those mining operations occurred without an approved plan
or plans of operations, and without a reclamation plan or
bond, where required.”

   [2] SREP’s allegations challenge specific instances of the
Forest Service’s actions taken pursuant to its interpretation of
MM-1, and therefore constitute more than a programmatic
attack or a vague reference to Forest Service action or inac-
tion. See Oregon v. Natural Desert Ass’n v. United States
Forest Serv., 465 F.3d 977, 990 (9th Cir. 2006). We therefore
reject the Forest Service’s arguments to the contrary, and con-
clude that, in light of SREP’s challenges to final agency
action, we have jurisdiction pursuant to 28 U.S.C. § 1291.8
  8
    In light of our determination that SREP challenges final agency action,
we need not address the “intra-circuit split” that we have recognized exists
on the question whether the “final agency action” requirement of the APA
is jurisdictional. See Gros Ventre Tribe v. United States, 469 F.3d 801,
809 (9th Cir. 2006).
             SISKIYOU REGIONAL EDUCATION v. USFS            5353
  Standard of Review

    We review de novo a grant of summary judgment. Native
Ecosystems Council v. United States Forest Serv., 418 F.3d
953, 960 (9th Cir. 2005) (citing Ground Zero Ctr. for Non-
Violent Action v. United States Dep’t of Navy, 383 F.3d 1082,
1086 (9th Cir. 2004)). The judicial review provisions of the
APA govern our review of agency decision-making under the
NFMA, because the NFMA does not contain an express pro-
vision for judicial review. Id. An agency decision may only
be set aside under the APA if it was “arbitrary, capricious, an
abuse of discretion, or otherwise not in accordance with law.”
Id.; 5 U.S.C. § 706(a). This standard, while “narrow,” none-
theless requires the court to “engage in a substantial inquiry[,]
. . . a thorough, probing, in-depth review.” Native Ecosystems
Council, 418 F.3d at 960. “[T]he agency must present a ratio-
nal connection between the facts found and the conclusions
made.” Id. (internal quotation marks omitted).

                       III.   DISCUSSION

  Standard and Guideline MM-1

   As noted above, the NFP specifies that none of the Stan-
dards and Guidelines, including MM-1, apply if they are con-
trary to existing law or regulation. Standards and Guidelines
at A-6, C-1. The Forest Service’s February 2002 Memoran-
dum to Regional Foresters interpreted MM-1 narrowly, con-
cluding that a broader interpretation would result in a conflict
between MM-1 and § 228.4(a). As we explain below, we
agree with the Forest Service that its interpretation of MM-1
is entitled to deference.

  Whether the Forest Service’s Interpretation is Entitled to
  Deference

   [3] “Agencies are entitled to deference to their interpreta-
tion of their own regulations, including Forest Plans.” Native
5354           SISKIYOU REGIONAL EDUCATION v. USFS
Ecosystems Council, 418 F.3d at 960 (citation and internal
quotations omitted); see also Hells Canyon Alliance v. United
States Forest Serv., 227 F.3d 1170, 1180 (9th Cir. 2000).
Indeed, although forest plans are adopted under 16 U.S.C.
§ 1604(a), we have effectively treated forest plan directives as
equivalent to federal regulations adopted under the APA,
deferring to the Forest Service’s interpretation of plan direc-
tives that are susceptible to more than one meaning unless the
interpretation is plainly erroneous or inconsistent with the
directive. See Forest Guardians v. United States Forest Serv.,
329 F.3d 1089, 1099 (9th Cir. 2003) (citing Thomas Jefferson
Univ. v. Shalala, 512 U.S. 504, 512 (1994)); Hells Canyon
Alliance, 227 F.3d at 1180 (citing Auer v. Robbins, 519 U.S.
452, 461 (1997)).9
   9
     This “plainly erroneous or inconsistent” standard is commonly referred
to as “Auer” deference, and is applied to agency interpretations of ambigu-
ous regulations. See Auer, 519 U.S. at 452 (holding that the Secretary of
Labor’s interpretation of its own ambiguous regulation was entitled to def-
erence); Bassiri v. Xerox Corp., 463 F.3d 927, 931 (9th Cir. 2006) (apply-
ing Auer deference to the Department of Labor’s interpretation of an
ambiguous regulation); Hells Canyon Alliance, 227 F.3d at 1180 (9th Cir.
2000) (“Because the [Land Resources Management] [P]lan language is
susceptible to more than one reasonable interpretation, we defer to the
agency’s interpretation.” (citing Auer, 519 U.S. at 461)).
   We have not explicitly relied on Auer in every case in which we have
concluded that the Forest Service’s interpretation of a forest plan was enti-
tled to deference. In Forest Guardians, for example, we cited to Thomas
Jefferson, not Auer, as providing the appropriate level of deference. Both
Forest Guardians and Hells Canyon Alliance, however, confirm that the
Forest Service’s interpretations of ambiguous forest plan directives—just
like agency interpretations of ambiguous regulations—are entitled to sig-
nificant deference. Indeed, the same case, Bowles v. Seminole Rock &
Sand Co., 325 U.S. 410, 414 (1945), provides the basis for both Jeffer-
son’s and Auer’s articulation of the proper degree of deference to an
ambiguous regulation, including forest plans. We are therefore satisfied
that the deferential standard set forth in Forest Guardians and in Hells
Canyon Alliance, whether referred to as Auer deference or not, describes
the proper degree of deference to which the Forest Service’s interpretation
of MM-1 is entitled.
             SISKIYOU REGIONAL EDUCATION v. USFS              5355
    [4] In contrast, where “neither the scope nor the effect” of
the regulation in question is ambiguous, “[t]here is no call for
deference to the agency’s legal interpretation.” Lands Council
v. Powell, 395 F.3d 1019, 1034 (9th Cir. 2005) (“The Forest
Service asserts that we owe its interpretation deference as a
reasonable interpretation of an ambiguity in a Forest Plan
. . . . There is no call for deference to the agency’s legal inter-
pretation of these two standards, however, because neither the
scope nor the effect of the two standards is ambiguous.” (cita-
tion omitted)); see also Christensen v. Harris County, 529
U.S. 576, 588 (2000) (“Auer deference is warranted only
when the language of the regulation is ambiguous.”). Thus, an
agency may not, “under the guise of interpreting a regulation,
. . . create de facto a new regulation.” Christensen, 529 U.S.
at 588. The fact that an agency’s interpretation has fluctuated
over time, however, does not make it unworthy of deference.
Kennedy v. Plan Adm’r for DuPont Sav. & Inv. Plan, 129
S. Ct. 865, 872 n.7 (2009) (citing Long Island Care at Home,
Ltd. v. Coke, 551 U.S. 158, 171 (2007)).

    1.    Ambiguity

   SREP contends that irrespective of the mandatory language
in MM-1, it is not contrary to the discretionary elements of
§ 228.4(a). According to SREP, “MM-1 simply makes the
decision for the line officer that mining in a riparian reserve
requires a plan of operations.” Thus, SREP argues, this blan-
ket requirement imposes a supplemental guideline that is con-
sistent with, not contrary to, § 228.4(a).

   Indeed, SREP points out that the Forest Service knew when
it was developing the NFP that MM-1 would significantly
limit mining operations in riparian reserves, and that MM-1
was in fact adopted to fulfill the Forest Service’s duties under
the NFMA to provide for a diversity of species. As support
for its position, SREP relies on statements in a draft of the
Forest Service’s Final Supplemental Environmental Impact
Statement for the NFP to show that it was intended to signifi-
5356        SISKIYOU REGIONAL EDUCATION v. USFS
cantly affect mining operations in order to protect wild
salmon:

    The development of mineral resources may be lim-
    ited by the land allocations and the standards and
    guidelines proposed in the alternatives. However, the
    more likely effect of designating areas for habitat for
    the northern spotted owl and other late-successional
    and old-growth related species would be that addi-
    tional measures to protect habitat would be required
    under mineral leases and in plans for locatable min-
    eral development.

Draft Final Supplemental Environmental Impact Statement,
Chapter 3&4, Affected Environment and Environmental Con-
sequences, SREP Excerpts of Record at 119.

   While SREP’s interpretation is not unreasonable, we agree
with the Forest Service’s assessment, as reflected in the Feb-
ruary 2002 memorandum, that the meaning of MM-1 is not
entirely “free from doubt.” Bassiri v. Xerox Corp., 463 F.3d
927, 931 (9th Cir. 2006) (quoting Providence Health Sys.-
Wash. v. Thompson, 353 F.3d 661, 665 (9th Cir. 2003)). The
first part of MM-1 requires plans of operations for all mineral
operations involving riparian reserves. This provision con-
flicts with § 228.4(a), which was adopted long before MM-1
and requires a plan of operations only when a district ranger
determines that the proposed mining operations will likely
cause significant disturbance of surface resources. That is,
while § 228.4(a) contemplates that a district ranger will
undertake a case-by-case determination of whether a plan of
operations is needed, MM-1 appears to impose such a require-
ment on all mining operations in riparian reserves.

   The second part of MM-1, however, as noted in the Febru-
ary 2002 memorandum, refers to recontouring of disturbed
areas, salvage and replacement of topsoil, and other details
that must be included in an approved plan of operations. This
               SISKIYOU REGIONAL EDUCATION v. USFS                    5357
provision of MM-1 appears to encompass the same threshold
standard as § 228.4(a), implying that only where the mining
operation poses a risk of significant surface disturbance will
a plan of operations or bond be required. The past disputes
over the meaning of MM-1 in light of § 228.4(a) further high-
light its opacity.10 See supra n.5; see also Bassiri, 463 F.3d at
931.

   [5] As previously noted, the NFP declares that any Stan-
dard and Guideline, including MM-1, shall not apply when
contrary to existing law or regulation. Because MM-1 is sus-
ceptible to different interpretations and given the discretion-
ary elements of § 228.4(a), we agree with the Forest Service
that MM-1 is ambiguous. It is not clear whether MM-1’s ref-
erence to all mining operations that include riparian reserves
applies to those mining operations that are not likely to cause
any significant disturbance of surface resources, or whether it
applies to every operation in these designated areas.

   [6] Thus, we will defer to the Forest Service’s interpreta-
tion of MM-1 unless it is plainly erroneous or inconsistent
with MM-1. “Under this standard, we defer to the agency’s
interpretation of its regulation unless an alternative reading is
compelled by the regulation’s plain language or by other indi-
cations of the agency’s intent at the time of the regulation’s
promulgation.” Bassiri, 463 F.3d at 931 (quoting Shalala, 512
U.S. at 512) (internal quotation marks omitted). The same rea-
sons that compel the conclusion that MM-1 is ambiguous lead
  10
    We note that in addition to the conflict over the meaning of MM-1
discussed in note 5, at least one other district court has weighed in on the
meaning of MM-1 in the context of the Klamath Forest Plan (“KFP”). See
Karuk Tribe of Cal. v. United States Forest Service, 379 F. Supp. 2d 1071,
1095 (N.D. Cal. 2005). In Karuk Tribe, the court upheld the Forest Ser-
vice’s interpretation of a directive contained in the KFP that incorporated
MM-1, concluding that “the Forest Service has consistently, and reason-
ably, interpreted the Northwest Forest Plan and Klamath Forest Plan to
address the inherent conflict between the mining regulations and the
Northwest Forest Plan.” Id. at 1098.
5358           SISKIYOU REGIONAL EDUCATION v. USFS
us to hold that the Forest Service’s narrow interpretation is a
reasonable reconciliation of MM-1 and § 228.4(a).

       2.   The Forest Service’s Interpretation of MM-1 Is Not
            Plainly Erroneous or Inconsistent with MM-1

   In light of the text of MM-1 and the binding force of the
NFP Standards and Guidelines, SREP’s mandatory interpreta-
tion would not be problematic if MM-1 were the only Forest
Service directive at issue. As previously noted, however, none
of the Standards and Guidelines—including MM-1—apply
“where they would be contrary to existing law or regulation.”

   Under SREP’s interpretation of MM-1, it requires a recla-
mation plan, approved plan of operations, and reclamation
bond “for all minerals operations that include Riparian
Reserves” (emphasis added). Section 228.4(a), in contrast,
provides that a plan of operations shall be required only “[i]f
the District Ranger determines that such operations will likely
cause significant disturbance of surface resources.” (emphasis
added). We agree with the Forest Service that § 228.4(a) pro-
vides that a plan of operations is required only when signifi-
cant disturbance of surface resources is likely—and therefore
one is not required when significant disturbance is not likely.
In other words, determining which operations are likely to
cause significant disturbance of surface resources—and there-
fore require a plan of operations—requires a discretionary
determination by a district ranger.11

  Neither by its express terms, nor as interpreted by SREP,
does MM-1 account for such a discretionary determination.
  11
    We note that the Department of Agriculture’s responses to public
comments that it invited before promulgating the 2005 version of
§ 228.4(a) emphasize the discretionary elements of the regulation. See 70
Fed. Reg. 32713, 32720 (June 6, 2005) (“The environmental impacts of
operating suction dredges, even small ones, are highly site-specific
depending on the circumstances and resource conditions involved.”).
            SISKIYOU REGIONAL EDUCATION v. USFS           5359
Instead, it eliminates discretion by requiring plans of opera-
tions for mining activity that might cause disturbance of sur-
face resources, yet are not likely to do so—and thus would
require only a notice of intent under 36 C.F.R. § 228.4(a). The
Forest Service’s February 2002 interpretation is a reasonable
effort to address and resolve the inconsistency between the
two directives.

   [7] We note that the Forest Service’s interpretation is also
consistent with Congress’s long-recognized interest in the
development of mineral resources. See 30 U.S.C. § 22 (“[A]ll
valuable mineral deposits in lands belonging to the United
States, both surveyed and unsurveyed, shall be free and open
to exploration and purchase . . . .”); see also 16 U.S.C. § 478
(acknowledging the Secretary of Agriculture’s authority under
16 U.S.C. § 551, and other provisions, to prescribe rules and
regulations to prevent “depredations upon the public forests
and national forests” but noting such authorization “shall not
be construed as prohibiting any person . . . from entering upon
such national forests for all proper and lawful purposes,
including that of prospecting, locating, and developing the
mineral resources thereof”); 30 U.S.C. §§ 611-12 (discussing
how the United States’s right to manage and dispose of vege-
tative surface rights must be balanced against the prospecting,
mining, or processing operations of miners). The Forest Ser-
vice acknowledges, and we have recognized, that mining
rights may not be unreasonably restricted in the performance
of Forest Service duties. See United States v. Shumway, 199
F.3d 1093, 1107 (9th Cir. 1999) (internal citation omitted).

   In sum, MM-1 is susceptible to several reasonable interpre-
tations. To adopt SREP’s interpretation would require a plan
of operations for every mining operation involving riparian
reserves, and would be contrary to § 228.4(a)’s specification
that a plan of operations is required only after the district
ranger so determines. The Forest Service’s narrow February
2002 interpretation of MM-1 is a reasonable attempt to recon-
cile the conflict between the two directives, and was neither
5360           SISKIYOU REGIONAL EDUCATION v. USFS
legally erroneous nor contrary to MM-1. We therefore defer
to the Forest Service’s interpretation, and affirm the grant of
summary judgment to the Forest Service.

                             IV.    BARTON

  Barton’s Motion to Intervene

   The district court granted Barton’s motion to intervene in
part, limiting intervention to the remedial phase of the litiga-
tion.12 Barton contends that he should have been granted inter-
vention in all phases of the litigation, either as of right under
Federal Rule of Civil Procedure 24(a), or permissively under
Rule 24(b).

   [8] Intervention on the merits would have allowed Barton
to present his argument that MM-1 is invalid because the For-
est Service lacks authority to regulate mining under the
NFMA. In light of our disposition of SREP’s appeal, how-
ever, there is no need for us to address whether the district
court erred by failing to allow Barton to intervene at the mer-
its stage of the litigation. Because there is no need for any fur-
ther district court proceedings, there is no need for us to
address Barton’s challenge to the district court’s ruling. We
therefore dismiss Barton’s appeal as moot. See League of
United Latin Am. Citizens v. Wilson, 131 F.3d 1297, 1301 &
n.1 (9th Cir. 1997); United States v. Ford, 650 F.2d 1141,
1142-43 (9th Cir. 1981).
  12
    WMD, which joined in Barton’s motion to intervene in the district
court, was denied leave to intervene at any stage in the litigation. On
appeal, however, WMD does not challenge the district court’s refusal to
allow it to intervene. Therefore, although WMD appealed the denial of its
motion, any challenge to the district court’s ruling is waived. See Eng, 552
F.3d at 1072.
            SISKIYOU REGIONAL EDUCATION v. USFS               5361
  Barton’s Separate Lawsuit

   The district court dismissed Barton’s separate suit, chal-
lenging the Forest Service’s authority to regulate mining
under the NFMA, as moot because he failed to allege actual
or potential injury. We agree.

   [9] “Mootness is a question of law reviewed de novo.” Bar-
ter Fair v. Jackson County, 372 F.3d 1128, 1133 (9th Cir.
2004) (citing Advocacy Ctr. v. Mink, 322 F.3d 1101, 1116
(9th Cir. 2003)). “The basic question in determining mootness
is whether there is a present controversy as to which effective
relief can be granted.” Serena v. Mock, 547 F.3d 1051, 1053
(9th Cir. 2008) (quoting Feldman v. Bomar, 518 F.3d 637,
642 (9th Cir. 2008)).

    A case becomes moot whenever it loses its character
    as a present, live controversy of the kind that must
    exist if we are to avoid advisory opinions on abstract
    propositions of law. The question is not whether the
    precise relief sought at the time . . . [the case] was
    filed is still available. The question is whether there
    can be any effective relief.

Earth Island Inst. v. United States Forest Serv., 442 F.3d
1147, 1157 (9th Cir. 2006) (citing Cantrell v. City of Long
Beach, 241 F.3d 674, 678 (9th Cir. 2001), abrogated on other
grounds by Winter v. Natural Res. Def. Council, Inc., 129
S. Ct. 365 (2008) (internal quotation marks and alterations
omitted)).

   [10] Barton contends that because the Forest Service’s cur-
rent interpretation of MM-1 could change, his suit falls within
the exception to the mootness doctrine reserved for voluntary
cessation of unlawful activity. See Friends of the Earth, Inc.
v. Laidlaw Envt’l Servs., Inc., 528 U.S. 167, 192 (2000). Bar-
ton, however, does not dispute that the Forest Service’s cur-
rent policy, as reflected in the February 2002 memorandum to
5362         SISKIYOU REGIONAL EDUCATION v. USFS
the Forest Rangers, is not to require a plan of operations for
mining activities unless such a plan would be required under
§ 228.4(a). Indeed, although the Forest Service does not dis-
pute that it may change its policy, the record does not indicate
that the Forest Service has any intention of changing its inter-
pretation of MM-1 to encompass mining activity beyond that
suggested by its current interpretation. Moreover, there is no
need, in light of our determination to affirm the district
court’s judgment in favor of the Forest Service—which ulti-
mately inheres to the benefit of Barton—to address the merits
of Barton’s separate claims.

  [11] In sum, the district court did not err in dismissing as
moot Barton’s separate suit, and we therefore affirm the
court’s ruling on this issue.

                    V.   HOBBS’S APPEAL

  [12] Finally, Hobbs appeals the district court’s grant of the
Forest Service’s motion to strike his answer to SREP’s
amended complaint and to assert his own “counterclaims.”
The district court determined that Hobbs’s arguments were
non-mandatory cross-claims against the Forest Service, and
were contrary to the district court’s earlier order restricting
Hobbs’s intervention to the “remedial phase” of the litigation.
We conclude that the district court’s decision to strike
Hobbs’s claims pursuant to Federal Rule of Civil Procedure
12(f) did not constitute an abuse of discretion. See Nurse v.
United States, 226 F.3d 996, 1000 (9th Cir. 2000).

   Although the district court granted Hobbs intervention only
as to the “remedial phase” of the litigation, his answer sought
to raise issues related to the merits of the litigation. Hobbs’s
“affirmative defenses” and “counterclaims” were either
defenses that the Forest Service could have raised in response
to SREP’s suit, or attempts to state independent claims against
the Forest Service. These claims exceeded the bounds of the
limited intervention granted to Hobbs. The district court’s rul-
             SISKIYOU REGIONAL EDUCATION v. USFS           5363
ing striking Hobbs’s answer was well within the court’s dis-
cretion and we therefore affirm the court’s ruling on this
issue.

   For the reasons stated, the judgment of the district court in
SREP’s action against the Forest Service is AFFIRMED. The
dismissal of Barton’s separate suit as moot is AFFIRMED.
Barton’s appeal in SREP’s action against the Forest Service
is DISMISSED as moot, and the striking of Hobbs’s answer
is AFFIRMED.

  AFFIRMED in part; DISMISSED in part.
