Bess Bair v. Cal. Dept of Transp.

FOR PUBLICATION

UNITED STATES COURT OF APPEALS
FOR THE NINTH CIRCUIT

BESS BAIR; TRISHA LEE LOTUS; No. 19-16478
JEFFREY HEDIN; DAVID SPREEN;
CENTER FOR BIOLOGICAL D.C. No.
DIVERSITY; ENVIRONMENTAL 3:17-cv-06419-
PROTECTION INFORMATION CENTER; WHA
CALIFORNIANS FOR ALTERNATIVES
TO TOXICS; FRIENDS OF DEL NORTE,
Plaintiffs-Appellees, OPINION

v.

CALIFORNIA DEPARTMENT OF
TRANSPORTATION; TOKS
OMISHAKIN, in his capacity as
Director of the California
Department of Transportation,
Defendants-Appellants.

Appeal from the United States District Court
for the Northern District of California
William Alsup, District Judge, Presiding

Argued and Submitted October 13, 2020
San Francisco, California

Filed December 2, 2020
2 BAIR V. CAL. DEP’T OF TRANSP.

Before: Ferdinand F. Fernandez, Kim McLane Wardlaw,
and Daniel P. Collins, Circuit Judges.

Opinion by Judge Fernandez;
Concurrence by Judge Wardlaw

SUMMARY*

Environmental Law

Reversing the district court’s judgment in favor of
plaintiffs, vacating an injunction, and remanding, the panel
held that the California Department of Transportation
complied with the National Environmental Policy Act in
relying on an Environmental Assessment for a proposed
highway improvement project within Richardson Grove State
Park.

Granting partial summary judgment in favor of plaintiffs,
the district court concluded that Caltrans had failed
adequately to consider certain issues and therefore had not
taken the requisite “hard look” at the environmental impacts
of the Project, and the 2010 Environmental Assessment (EA),
as supplemented and revised, was inadequate. The district
court concluded that substantial questions had been raised as
to the effects of the Project, and it ordered Caltrans to prepare
an environmental impact statement (EIS). The district court
enjoined Caltrans from proceeding with the Project until the
EIS was finalized.

*
This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
 BAIR V. CAL. DEP’T OF TRANSP. 3

Reversing, the panel held that Caltrans based its 2017
finding of no significant impact (FONSI) upon the analysis
contained in the revised EA, which incorporated the analysis
of the 2010 EA and the 2013 Revised Supplemental EA.
Because Caltrans’ 2010 EA, as supplemented and revised,
constituted the “hard look” at the Project’s effects required by
NEPA, Caltrans’ issuance of the 2017 FONSI was
reasonable. The panel held that none of the purported
inadequacies identified by the district court rendered the
revised EA arbitrary or capricious.

Concurring, Judge Wardlaw wrote that she concurred in
the majority opinion, and Caltrans did not violate NEPA
because its reliance on the EA was not arbitrary and
capricious. Judge Wardlaw wrote separately to emphasize
that: (1) the administrative record was painful to review;
(2) if significant new information is discovered during the
proposed construction or substantial project changes are
made, Caltrans may need to reevaluate its analysis; and
(3) the Project seems likely to provide new data on the effects
of construction on old-growth redwoods, which could prove
important to future decisions surrounding these historic trees.

COUNSEL

Stacy Jayne Lau (argued), Michael A.G. Einhorn, and Angela
Wuerth; Lucille Y. Baca, Assistant Chief Counsel;
G. Michael Harrington, Deputy Chief Counsel; Erin E.
Holbrook, Chief Counsel; State of California Department of
Transportation – Legal Division, Oakland, California; for
Defendants-Appellants.
4 BAIR V. CAL. DEP’T OF TRANSP.

Stuart G. Gross (Argued) and Timothy S. Kline, Gross &
Klein LLP, San Francisco, California; Todd R. Gregorian and
Garner F. Kropp, Fenwick & West LLP, San Francisco,
California; for Plaintiffs-Appellees.

OPINION

FERNANDEZ, Circuit Judge:

This environmental appeal arises from a highway
improvement project proposed by the California Department
of Transportation (collectively with its director, Toks
Omishakin, Caltrans). Plaintiffs Bess Bair, Trisha Lee Lotus,
Jeffrey Hedin, David Spreen, the Center for Biological
Diversity, the Environmental Protection Information Center,
Californians for Alternatives to Toxics, and Friends of del
Norte (collectively, Bair1) challenged the project on a variety
of grounds, including the failure to comply with the National
Environmental Policy Act of 1969, Pub. L. No. 91–190, 83
Stat. 852 (1970) (NEPA). The district court determined that
Caltrans arbitrarily and capriciously relied upon the 2010
Environmental Assessment (2010 EA), as supplemented and
revised, because, it held, that document failed to sufficiently
consider certain “significant issues.” Bair v. Cal. State Dep’t
of Transp., 385 F. Supp. 3d 878, 886 (N.D. Cal. 2019). The
district court also enjoined Caltrans from continuing the
project until it finalized an appropriate environmental impact
statement (EIS). It then entered a final judgment against
Caltrans. We reverse and remand.

1
While the plaintiffs other than Bair have changed from time to time
during the more than ten years of litigation that has ensued, unless
otherwise noted, the plaintiffs will hereafter be referred to as Bair.
 BAIR V. CAL. DEP’T OF TRANSP. 5

I. BACKGROUND

Richardson Grove State Park (the Grove) comprises
approximately 2,000 acres within the redwood forests of
southern Humboldt County, California, and is bisected by
United States Highway 101. Within the Grove, Highway 101
is a two-lane highway “on a nonstandard alignment” with
tight curves and narrow travel lanes and roadway shoulders.
A number of trees, including old-growth redwood trees,2 abut
the roadway as it meanders through the Grove. In light of
antiquated roadway design, there are restrictions on the types
of vehicles that may travel that portion of the highway.
Sixty-five foot long “California Legal” trucks are permitted,
but industry-standard Surface Transportation Assistance Act
of 19823 (STAA) trucks generally are not. STAA trucks are
longer than California Legal trucks and can carry larger cargo
volumes, although both classes of trucks are subject to the
same weight limitation. Because of their longer length,
STAA trucks navigating the highway’s tight curves
frequently “off-track” into the opposing traffic lane or onto
the roadway shoulder.

The STAA truck restriction at the Grove is the only
remaining impediment to STAA trucks traveling into
Humboldt County via Highway 101. Caltrans has long
sought to remove that roadblock, but abandoned previous
efforts because of the substantial projected expense, among
other things. In 2007, Caltrans learned that the existing
roadway could be strategically widened to render it accessible

2
Caltrans defined “old growth redwood[s]” as “trees over 30 inches
in diameter at breast height (4.5 feet above ground level).”
3
Pub. L. No. 97–424, 96 Stat. 2097 (1983).
6 BAIR V. CAL. DEP’T OF TRANSP.

to STAA trucks, and Caltrans developed the Richardson
Grove Operational Improvement Project (the Project) to do
just that. The Project involves slightly widening the roadway
and straightening some curves in certain locations along a
one-mile stretch of Highway 101, largely within the Grove.
Its purposes are to accommodate STAA truck travel, improve
the safety and operation of Highway 101, and improve the
movement of goods into Humboldt County. The speed limit
would remain unchanged at thirty five miles per hour.
Caltrans assumed responsibility for obtaining environmental
approval for the Project pursuant to NEPA. See 23 U.S.C.
§ 327(a)(2)(A), (B)(i).

A. The Project as originally proposed in 2010

The original 2010 EA included extensive analysis of the
Project’s environmental effects and efforts to minimize those
effects (developed in consultation with the California
Department of Parks and Recreation (State Parks)). More
than 100 pages of the 2010 EA were devoted to analyzing
various environmental impacts, such as the effects on the
nearby South Fork Eel River, the Grove and its recreation
facilities, economic growth, traffic, water quality, noise, local
plant and animal species (particularly old-growth redwood
trees), and protected or threatened species.

Caltrans ultimately determined that the impacts to the
Grove would be minor, and would primarily consist of “tree
removal resulting from cuts and fills that are necessary to
accommodate the highway improvements,” as well as the
 BAIR V. CAL. DEP’T OF TRANSP. 7

effect on trees whose structural root zones4 were within the
construction area. Although some trees would be removed,
none of those would be old-growth redwoods. And while
construction would occur in the structural root zones of fewer
than 80 old-growth redwoods, plans were made to mitigate its
effects. For example, Caltrans proposed to increase the
height of the roadbed where possible to avoid severing tree
roots, use a thinner roadbed material to allow greater
permeability, conduct some construction (excavation) by
hand, water trees during the summer, and remove some
invasive plants. In light of those measures, both the Caltrans
arborist (Darin Sullivan) and the arborist hired by Save the
Redwoods League (Dennis Yniguez) determined that the
Project as proposed in 2010 “would not significantly impact
the root health of the old growth trees adjacent to the
construction.” Caltrans issued the EA and Finding of No
Significant Impact (FONSI) for the Project in May 2010.

B. Past litigation

Bair filed suit regarding the Project in both 20105 and
2014,6 each time making similar claims. In the First
Litigation, the district court granted partial summary
judgment to the plaintiffs and ordered Caltrans to undertake

4
As defined in the 2010 EA, “the structural root zone is a circular
area with the tree trunk at the center with a radius equal to three times the
diameter of the tree trunk measured at 4.5 feet above ground level,” and
“is where most of the [tree’s] nutrient and water absorption occurs.”
5
Bair v. Cal. Dep’t of Transp., No. 3:10-cv-04360-WHA (N.D. Cal.
2010) (the First Litigation).
6
Bair v. Cal. Dep’t of Transp., No. 3:14-cv-03422-WHA (N.D. Cal.
2014) (the Second Litigation).
8 BAIR V. CAL. DEP’T OF TRANSP.

additional studies, such as preparing new maps of each old-
growth redwood tree, its root health zone, and the
environmental impacts to each tree. Bair, 385 F. Supp. 3d
at 883. Caltrans then revised its analysis accordingly. After
commissioning a tree report from arborist Yniguez, it issued
a 2013 Supplement to the 2010 EA. Caltrans then took public
comments, responded to them, and finally issued a NEPA Re-
validation for the Project in January 2014. It found that the
2010 EA and FONSI remained valid.

In the Second Litigation, Bair challenged the re-validated
Project on many of the same grounds as in the First
Litigation. See id. The Second Litigation was dismissed after
Caltrans withdrew the FONSI7 in light of an adverse ruling in
a parallel proceeding in the California Court of Appeal. See
Bair, 385 F. Supp. 3d at 883–84; Lotus v. Dep’t of Transp.,
167 Cal. Rptr. 3d 382, 393 (Ct. App. 2014). In response to
the California court’s order, Caltrans slightly reduced the
scope of the Project, and Yniguez prepared another tree
report.

C. 2017 Project proposal and current litigation

Since the original issuance of the EA in 2010, Caltrans
has modified the Project to reduce its impact, primarily by
narrowing the proposed roadbed (roadway shoulders). The
Project now requires the removal of 38 trees, none of which
are old-growth redwoods, and construction will occur within
the structural root zones of 78 old-growth redwood trees,
72 of which are within the Grove. That construction activity
largely consists of (1) excavation to a maximum depth of two

7
Notice of Rescission of Finding of No Significant Impact, 79 Fed.
Reg. 70,612-01, 70,612 (Nov. 26, 2014).
 BAIR V. CAL. DEP’T OF TRANSP. 9

feet; (2) covering some of the root zone with impervious
surface (roadbed); and (3) placing fill over tree roots. As
noted, Caltrans retained arborist Yniguez to evaluate the
effects of the Project on the redwoods and to produce two
reports summarizing his conclusions. In general, he
determined that the Project “would not have any substantial
detrimental effect on individual old-growth redwoods . . . or
the overall health of the stand of redwoods in Richardson
Grove.” His reports were based on scientific literature
regarding redwoods, his three decades of experience as an
arborist, multiple site visits to the Grove (including a
helicopter flight to evaluate tree crowns), and materials
provided by Caltrans such as the EA, detailed schematic
drawings of all trees with root zones within the Project area,
and individual tree details for each. Yniguez assessed each
tree individually to determine the likely effect on its health
from the root zone disturbances created by the Project, both
with and without mitigation measures, and assigned each tree
a rating corresponding to the anticipated effects on its health,
ranging from Level 0 to Level 6. He concluded that the
Project would not jeopardize the lives of any old-growth
redwood trees, and that the vast majority of such trees would
sustain no decline in foliage density or health as a result of
the Project. In the absence of mitigation measures, Yniguez
decided that approximately eighteen old-growth redwood
trees may manifest “a short-term visible reduction in foliage
density that is still well within the adaptive capabilities of the
tree” (Level 4 rating), while one such tree may undergo “a
reduction in root health sufficient to cause lasting visible
dieback of wood in the uppermost crown, although tree health
and survival [would] not [be] threatened” (Level 5 rating).
Including the Project’s mitigation measures substantially
reduced those effects: Yniguez determined that only three
old-growth redwood trees would remain in Level 4 and none
10 BAIR V. CAL. DEP’T OF TRANSP.

in Level 5 if the proposed mitigation measures were
implemented. Yniguez thus concluded that “[n]one of the
proposed highway alterations is of sufficient magnitude to
threaten the health or stability of any old-growth redwood”
because “disturbances would be confined to a small
percentage of the area occupied by roots and would be well
within the adaptive capabilities of the tree[s].” Moreover,
even without mitigation measures, Yniguez concluded that
“the limited root disturbance would be inconsequential to the
appearance, stability, and continued health of the old-growth
redwoods in Richardson Grove.”

Caltrans largely agreed with Yniguez’s analysis, but also
considered other evidence, such as scientific literature about
the resilience, health, and development of redwoods and their
root systems generally, the condition of the particular old-
growth redwood trees in the Project area, and the specific
activities and mitigation measures comprising the Project.
Caltrans thus concluded that “[i]n no case would root
disturbance have a significant detrimental effect on the health
or stability of old-growth redwoods.” In May 2017, Caltrans
issued revisions to the EA and a new FONSI.

Bair filed this litigation in 2017,8 again raising claims
similar to those that had been made in the First Litigation and
the Second Litigation, specifically: seven claims alleging
various violations of NEPA, as well as claims for a violation
of section 4(f) of the Department of Transportation Act,9 a

8
Bair v. Cal. Dep’t of Transp., No. 3:17-cv-06419-WHA (N.D. Cal.
2017).
9
23 U.S.C. § 138(a); see also 23 C.F.R. § 774.1.
 BAIR V. CAL. DEP’T OF TRANSP. 11

violation of section 7 of the Wild and Scenic Rivers Act,10 a
violation of the Administrative Procedure Act (APA),11 a
declaration that Caltrans is responsible for Bair’s attorney’s
fees and costs,12 and injunctive relief.13 The district court
granted Bair partial summary judgment as to some of the
NEPA claims. Bair, 385 F. Supp. 3d at 898.14 The district
court identified certain issues that, in its view, Caltrans had
not adequately considered: whether (1) redwoods would
suffocate when more than half of their root zones were
covered by pavement;15 (2) construction in a redwood’s
structural root zone would cause root disease;16 (3) traffic
noise would increase because of the larger size of the STAA
trucks or because of additional numbers of trucks;17 and
(4) redwoods would suffer more frequent and severe damage
as a result of strikes by STAA trucks.18 Because of those
deficiencies, the district court determined that Caltrans had
not taken the requisite “hard look” at the environmental
impacts of the Project, and that the EA was inadequate. Id.

10
16 U.S.C. § 1278(a).
11
5 U.S.C. § 706(2)(A), (D).
12
See 23 U.S.C. § 327(a)(2)(G); Cal. Civ. Proc. Code § 1021.5.
13
Fed. R. Civ. P. 65(a).
14
The district court did not address Bair’s other claims. See id.
15
Id. at 886, 888.
16
Id. at 891.
17
Id. at 892–93, 895.
18
Id. at 895.
12 BAIR V. CAL. DEP’T OF TRANSP.

at 890–91, 895, 898. In light of those supposed shortcomings
in the EA, the district court concluded that substantial
questions had been raised as to the effects of the Project, and
it ordered Caltrans to prepare an EIS. The district court also
enjoined Caltrans from proceeding with the Project until the
EIS was finalized. Caltrans timely appealed. See Fed. R.
App. P. 4(a)(1)(A).

II. JURISDICTION

The district court had jurisdiction pursuant to 28 U.S.C.
§ 1331. We have jurisdiction. 28 U.S.C. § 1291; see
HonoluluTraffic.com v. Fed. Transit Admin., 742 F.3d 1222,
1229 (9th Cir. 2014); Alsea Valley All. v. Dep’t of Com.,
358 F.3d 1181, 1184 (9th Cir. 2004).

III. STANDARDS OF REVIEW

“We review de novo a district court’s grant of summary
judgment.” Am. Wild Horse Campaign v. Bernhardt,
963 F.3d 1001, 1007 (9th Cir. 2020). “[A]gency decisions
that allegedly violate NEPA” are reviewed “under the
Administrative Procedure Act, and we set aside those
decisions only if they are ‘arbitrary, capricious, an abuse of
discretion, or otherwise not in accordance with law.’” Id.; see
also 5 U.S.C. § 706(2)(A). “Whether a plaintiff has
exhausted required administrative remedies is a question of
law reviewed de novo.” Great Basin Mine Watch v. Hankins,
456 F.3d 955, 961 (9th Cir. 2006).

IV. DISCUSSION

NEPA generally “requires a federal agency . . . to prepare
‘a detailed statement on . . . the environmental impact’ of
 BAIR V. CAL. DEP’T OF TRANSP. 13

‘major Federal actions significantly affecting the quality of
the human environment,’”19 a document known as an EIS.20
However, the regulations alternatively “allow an agency to
prepare a more limited document, an Environmental
Assessment (EA), if the agency’s proposed action . . . would
[not] clearly require the production of an EIS.” Dep’t of
Transp. v. Pub. Citizen, 541 U.S. 752, 757, 124 S. Ct. 2204,
2209–10, 159 L. Ed. 2d 60 (2004); see also 40 C.F.R.
§ 1501.4(b)–(c). An EA is “a ‘concise public document’ that
‘[b]riefly provide[s] sufficient evidence and analysis for
determining whether to prepare an [EIS].’” Dep’t of Transp.,
541 U.S. at 757, 124 S. Ct. at 2210; see also Ctr. for
Biological Diversity, 538 F.3d at 1185; 40 C.F.R.
§ 1508.9(a)–(b).

If the “agency determines that an EIS is not required . . . ,
it . . . issue[s] a ‘finding of no significant impact’ (FONSI),
which briefly presents the reasons why the proposed agency
action will not have a significant impact on the human
environment.” Dep’t of Transp., 541 U.S. at 757–58, 124 S.
Ct. at 2210; see also 40 C.F.R. §§ 1501.4(e), 1508.13. That
decision “can be set aside only upon a showing that it was

19
Ctr. for Biological Diversity v. Nat’l Highway Traffic Safety
Admin., 538 F.3d 1172, 1185 (9th Cir. 2008); see also 42 U.S.C.
§ 4332(C).
20
See 40 C.F.R. § 1501.4(a), (c). The Council on Environmental
Quality has adopted new regulations that became effective on September
14, 2020. Update to the Regulations Implementing the Procedural
Provisions of the National Environmental Policy Act, 85 Fed. Reg.
43,304, 43,304 (July 16, 2020); see also 40 C.F.R. § 1506.13 (2020).
Because Caltrans applied the previous regulations to the Project, so do we.
Unless otherwise indicated, the regulations cited herein are the versions
in effect when the district court rendered its decision.
14 BAIR V. CAL. DEP’T OF TRANSP.

‘arbitrary, capricious, an abuse of discretion, or otherwise not
in accordance with law.’” Dep’t of Transp., 541 U.S. at 763,
124 S. Ct. at 2213; see also 5 U.S.C. § 706(2)(A); Ocean
Advocs. v. U.S. Army Corps of Eng’rs, 402 F.3d 846, 858 (9th
Cir. 2005). Determining whether the agency’s decision not
to prepare an EIS was arbitrary and capricious “requires us to
determine whether the agency has taken a hard look at the
consequences of its actions, based [its decision] on a
consideration of the relevant factors, and provided a
convincing statement of reasons to explain why a project’s
impacts are insignificant.” Native Ecosystems Council v. U.S.
Forest Serv. (Native Ecosystems I), 428 F.3d 1233, 1239 (9th
Cir. 2005) (internal quotation marks omitted). Although our
review “is ‘searching and careful,’” it is nevertheless
narrowly circumscribed, “and we cannot substitute our own
judgment for that of the [agency].” Ocean Advocs., 402 F.3d
at 858. Instead, “[w]e ask ‘whether the [agency’s] decision
was based on a consideration of the relevant factors and
whether there has been a clear error of judgment.’” Id. at
859; see also In Def. of Animals v. U.S. Dep’t of the Interior,
751 F.3d 1054, 1072 (9th Cir. 2014). But we must keep in
mind that we are not “a panel of scientists that instructs the
[agency] how to validate its hypotheses . . . , chooses among
scientific studies . . . , [or] orders the agency to explain every
possible scientific uncertainty.” Lands Council v. McNair,
537 F.3d 981, 988 (9th Cir. 2008) (en banc), overruled in part
on other grounds by Winter v. Nat. Res. Def. Council, Inc.,
555 U.S. 7, 21–22, 129 S. Ct. 365, 375, 172 L. Ed. 2d 249
(2008).

Caltrans based its 2017 FONSI upon the analysis
contained in the revised EA, which incorporated the analysis
of the 2010 EA and the 2013 Revised Supplemental EA.
Because Caltrans’ 2010 EA, as supplemented and revised,
 BAIR V. CAL. DEP’T OF TRANSP. 15

constituted the “hard look” at the Project’s effects required by
NEPA, Caltrans’ issuance of the 2017 FONSI was
reasonable. The district court erred in granting partial
summary judgment to Bair. As we explain in the ensuing
paragraphs, none of the purported inadequacies it identified
rendered the revised EA arbitrary or capricious.

First, as to redwood tree suffocation, Caltrans sufficiently
considered the effect of paving over portions of tree root
zones. The Project will use a special material to allow
“‘greater porosity’” and to “‘promote air circulation’” under
the asphalt,21 and Caltrans considered the aggregate amount
of new roadbed material that would be placed over the
structural root zones. Yniguez specifically relied in part upon
Caltrans’ selection of permeable material, the minor and
limited areas of new asphalt, and Caltrans’ decision to narrow
the proposed roadway shoulders where possible in reaching
his conclusion that the Project would not create extreme
stress in the redwoods or overwhelm their natural resilience.22
And, as more particularly described in Part I.C of this
Opinion, Yniguez and Caltrans thoroughly assessed the
amount of paving that would be placed over the root zone of
each tree. Caltrans considered the possibility that paving
could harm the trees, but simply (and reasonably) concluded
that there was sufficient evidence to the contrary. See In Def.

21
Bair, 385 F. Supp. 3d at 888.
22
Caltrans reasonably relied upon Yniguez’s reports, and Bair does
not argue otherwise. See Native Ecosystems Council v. Weldon (Native
Ecosystems II), 697 F.3d 1043, 1051–52 (9th Cir. 2012). Caltrans’
reliance on evidence specifically pertaining to redwoods (including
Yniguez’s reports) was eminently reasonable, especially because the
record reflects that redwood trees and their root systems are particularly
(uniquely) resilient.
16 BAIR V. CAL. DEP’T OF TRANSP.

of Animals, 751 F.3d at 1072; Lands Council, 537 F.3d at
1003. That was not arbitrary or capricious. See In Def. of
Animals, 751 F.3d at 1072–73.23 The district court erred in
concluding that the EA failed to adequately consider the
effects of paving over portions of the root zones of certain
trees.

Second, as to construction within root zones, Caltrans
appropriately considered the extent and effect of the
construction activity that would occur in the structural root
zones of redwood trees, including construction guidelines in
a State Parks handbook. The record plainly belies Bair’s
contention that Caltrans failed to consider the effects of
construction. On the contrary, as described in Part I of this
Opinion, the record is replete with Caltrans’ comprehensive
analyses of the extent and effects of construction activity in
the root zones of individual trees. See Cold Mountain v.
Garber, 375 F.3d 884, 893–94 (9th Cir. 2004).24 As to the

23
Moreover, there is no evidence supporting the district court’s
assumption that 50% paving over root zones is some sort of “threshold”
demarcating a “‘danger zone’” or “red zone” for redwood trees. Bair,
385 F. Supp. 3d at 888–89. Rather, that is an unwarranted inference
drawn from a misreading of evidence in the record. Indeed, no comments
or evidence in the administrative record raised the 50% threshold issue.
That suggests that the issue was not even administratively exhausted. See
Barnes v. U.S. Dep’t of Transp., 655 F.3d 1124, 1132, 1135–36 (9th Cir.
2011).
24
The district court erred in criticizing Caltrans for failing to consider
whether root disease would arise from root injuries caused by
construction. See Bair, 385 F. Supp. 3d at 891. Caltrans reasonably relied
upon its expert’s opinion that redwoods have “no important . . . disease
enemies”—evidence tailored to redwoods specifically, rather than trees in
general. See In Def. of Animals, 751 F.3d at 1072; City of Carmel-By-The-
Sea v. U.S. Dep’t of Transp., 123 F.3d 1142, 1151 (9th Cir. 1997).
 BAIR V. CAL. DEP’T OF TRANSP. 17

sentence in State Parks’ handbook that recommended that no
construction should take place in the structural root zone “of
a protected tree,” it is not clear that it applied to the affected
redwoods or influenced State Parks’ opinion of the Project, or
that Caltrans was obligated to defer to or adopt that opinion.
See WildEarth Guardians v. Provencio, 923 F.3d 655, 672
(9th Cir. 2019); see also Native Ecosystems I, 428 F.3d
at 1242. NEPA anticipates that the administrative record may
contain contradictory and conflicting opinions, expert and
otherwise,25 and does not require an agency to follow all
recommendations made by commentators, other agencies, or
experts.26 Thus, to the extent that the recommendation in
State Parks’ handbook is relevant here, Caltrans could (and
did) reasonably refuse to follow it, especially when Caltrans
relied upon evidence specifically pertaining to the effects of
construction on redwoods in general and the redwoods in the
Project area, in particular. In fine, the district court erred
when it decided that Caltrans failed to sufficiently consider
the State Parks handbook and the impact of construction in
the structural root zones of old-growth redwoods.

Third, as to traffic volume and noise, the district court
erred when it decided that Caltrans failed to adequately
consider how the visitor experience to the Grove would be
affected by the presence of STAA trucks, particularly with
regard to whether they would be more numerous or generate
more noise. Bair, 385 F. Supp. 3d at 891–92, 895. Caltrans’
EA concluded that truck traffic would not increase as a result
of the Project, and it properly relied upon record evidence to

25
City of Carmel-By-The-Sea, 123 F.3d at 1151; see also In Def. of
Animals, 751 F.3d at 1072.
26
See WildEarth Guardians, 923 F.3d at 672.
18 BAIR V. CAL. DEP’T OF TRANSP.

do so, including: a survey of regional business owners, traffic
studies in nearby areas suggesting little latent demand for the
route, the fact that highway capacity would be unchanged,
and Caltrans’ opinion that STAA trucks currently using the
straighter alignment and faster travel time of Interstate 5 to
reach major coastal cities were unlikely to detour through the
Grove. See In Def. of Animals, 751 F.3d at 1072. Caltrans
reasonably concluded from that evidence that traffic would
not increase as a result of the Project. Thus, Caltrans’
conclusion that traffic would not increase is entitled to
deference. See WildEarth Guardians, 923 F.3d at 672; Native
Ecosystems II, 697 F.3d at 1052–53; cf. Ocean Advocs.,
402 F.3d at 865–66 (agency failed to consider possible traffic
increase). Moreover, in light of its conclusion that truck
traffic would not increase, Caltrans also reasonably concluded
that traffic noise would not appreciably increase. Although
the district court stated that it believed STAA trucks would be
noisier than California Legal trucks because their tractor units
“are bigger and heavier,”27 it cited no evidence for its
assumptions about the size and weight of STAA tractor units,
or its belief about their noise in comparison to California
Legal trucks. Nor have we been pointed to any evidence of
that in the record. A district court has no more license to act
as “a panel of scientists” than we have. Lands Council,
537 F.3d at 988. Caltrans adequately considered the Project’s
effects on both traffic and traffic noise in the Grove, and
reasonably concluded that the impacts would not be
significant.

Fourth, as to collisions with trees, the district court erred
by determining that Caltrans should have analyzed whether
the Project could cause trees to: suffer more frequent

27
Bair, 385 F. Supp. 3d at 894–95.
 BAIR V. CAL. DEP’T OF TRANSP. 19

collisions with trucks because STAA trucks are longer and
more difficult to maneuver; and sustain more damage from
collisions because STAA trucks are heavier and their engine
compartments more protruding than California Legal trucks.
Bair, 385 F. Supp. 3d at 895. Caltrans’ analysis was not
arbitrary and capricious. See Lands Council, 537 F.3d at 993.
As to collision frequency, the undisputed purpose of the
Project is to widen the road in order to provide room for off-
tracking STAA trucks, and Caltrans reasonably concluded
that doing so would decrease the incidence of vehicles
colliding with trees. Bair’s assumption that the collision risk
will increase because the pavement will be closer to some
trees ignores that the pavement is moving farther from other
trees.28 Caltrans’ conclusions regarding the frequency of
collisions were reasonable and entitled to deference,
especially because they pertain to an “area[] of agency
expertise.” Nat’l Parks & Conservation Ass’n v. U.S. Dep’t
of Transp., 222 F.3d 677, 682 (9th Cir. 2000); see also Lands
Council, 537 F.3d at 993.

As to damage severity, we have not located any
comments or documents in the administrative record which
indicate that STAA trucks would cause more damage when
they strike trees. Thus, it appears that issue was not
administratively exhausted. See Barnes, 655 F.3d at 1132,
1135–36. And even if the issue had been exhausted, the
district court’s speculation that trees would suffer more
severe damage from collisions because of the weight or shape
of STAA trucks is not supported by any evidence in the

28
It also ignores record evidence suggesting that the number of trucks
traveling through the Grove may actually decrease because some of the
California Legal trucks that would otherwise drive through the Grove may
be replaced by fewer STAA trucks.
20 BAIR V. CAL. DEP’T OF TRANSP.

record. It was reasonable for Caltrans’ EA not to anticipate
that unfounded speculation. See Lands Council, 537 F.3d
at 1002. We reject Bair’s argument that because Caltrans was
responsible for drafting the EA, it was also required to amass
evidence demonstrating the comparative damage caused to
trees by collisions with STAA trucks and California Legal
trucks. See 40 C.F.R. § 1508.9(a). While it is arbitrary and
capricious for an agency to “‘entirely fail[] to consider an
important aspect of the problem,’” that did not occur here.
Lands Council, 537 F.3d at 993. As described above,
Caltrans considered the effects of the Project with regard to
traffic volume, noise, ease of navigation, and tree collisions.
An agency is not required “to address in detail . . . every
single comment . . . to prove that [it] ‘considered’ the relevant
factors,”29 much less to anticipate conclusory supposition
about speculative and tangential effects that are not supported
by evidence in the record.30

For those reasons, we are satisfied that Caltrans took a
hard look at the consequences of the Project, and adequately
considered the relevant factors. See Native Ecosystems I,
428 F.3d at 1239. That Bair or the district court may disagree
with Caltrans’ conclusions “does not constitute a NEPA
violation.” Native Ecosystems II, 697 F.3d at 1053; see also
WildEarth Guardians, 923 F.3d at 672. Thus, the district
court erred in finding Caltrans’ EA arbitrary and capricious
and in setting aside the 2017 FONSI.

29
In Def. of Animals, 751 F.3d at 1072.
30
See WildEarth Guardians, 923 F.3d at 672; Native Ecosystems II,
697 F.3d at 1053, 1055; see also Am. Wild Horse Campaign, 963 F.3d
at 1008–10.
 BAIR V. CAL. DEP’T OF TRANSP. 21

In light of our conclusion, we reverse the district court’s
judgment requiring Caltrans to produce an EIS and enjoining
it from continuing the Project until it has done so. An agency
must prepare an EIS “[i]f there is a substantial question
whether an action ‘may have a significant effect’ on the
environment.” Ctr. for Biological Diversity, 538 F.3d
at 1185; see also 42 U.S.C. § 4332(C); 40 C.F.R. §§ 1502.1,
1508.18, 1508.27. The district court’s rationale for requiring
an EIS was predicated on its erroneous conclusions about the
Project’s effects on redwood tree health and possible
increases in truck traffic and noise. Because we have
determined that the EA’s analysis was adequate in those
respects, the district court necessarily erred in setting aside
the 2017 FONSI and ordering Caltrans to prepare an EIS if it
desired to proceed. See Dep’t of Transp., 541 U.S. at 762–64,
124 S. Ct. at 2212–13.31

V. CONCLUSION

The parties have engaged in contentious litigation over
the (relatively limited) Project for more than ten years.
However, Caltrans’ environmental analyses regarding the
redwoods and traffic satisfied NEPA’s requirements.
Therefore, we reverse the district court’s judgment, and we
vacate the injunction.

While we have now resolved those aspects of the parties’
dispute, Bair’s other claims regarding defects in Caltrans’

31
Caltrans invites us to exercise our discretion to resolve Bair’s other
claims, which the district court did not reach when it entered final
judgment against Caltrans. See Bair, 385 F. Supp. 3d at 898. We decline
the invitation. See Davis v. Nordstrom, Inc., 755 F.3d 1089, 1094–95 (9th
Cir. 2014).
22 BAIR V. CAL. DEP’T OF TRANSP.

consideration of other issues remain unresolved because the
district court’s order that Caltrans must prepare an EIS made
it unnecessary to do so. We expect that the district court will
now expeditiously consider and dispose of those remaining
claims on remand.

REVERSED and REMANDED for further
proceedings not inconsistent with this Opinion.

WARDLAW, Circuit Judge, concurring

“Although the environmental assessment did not always
make [Caltrans’s] reasoning explicit” and is “a decision of
less than ideal clarity,” “the agency’s path may reasonably be
discerned.” Am. Wild Horse Campaign v. Bernhardt,
963 F.3d 1001, 1009 (9th Cir. 2020). Therefore, in light of
the administrative record in this case, I concur in the majority
opinion. Caltrans did not violate NEPA because its reliance
on the EA was not arbitrary and capricious. I write separately
to emphasize three points.

First, reviewing the “nightmarish ‘administrative record’
in this case was a painful exercise. Bair v. Cal. State Dep’t
of Transp., No. C 17-06419 WHA, 2019 WL 2644074, at *5
(N.D. Cal. June 27, 2019). When resolving the remaining
claims on remand, the district court’s suggestion that Caltrans
provide a “fresh administrative record . . . with no
incorporations by reference” seems sensible. Id. at *5.

Second, and as Caltrans’s counsel acknowledged at oral
argument, if “significant new information is discovered”
during the proposed construction or if “substantial project
 BAIR V. CAL. DEP’T OF TRANSP. 23

changes are made,” Recording of October 13, 2020 Oral
Argument at 17:10–17:42,1 Caltrans may well need to
reevaluate its analysis and potentially prepare an additional
revised EA or even an EIS. See 23 C.F.R. §§ 771.129,
771.130; see also Idaho Sporting Congress Inc. v. Alexander,
222 F.3d 562, 566 n.2 (9th Cir. 2000) (“NEPA imposes on
federal agencies a continuing duty to supplement existing
EAs and EISs in response to significant new circumstances or
information relevant to environmental concerns and bearing
on the proposed action or its impacts.” (internal quotation
marks and citation omitted)); Price Road Neighborhood
Ass’n, Inc. v. U.S. Dep’t of Transp., 113 F.3d 1505, 1510 (9th
Cir. 1997) (examining the FHWA NEPA framework and the
continuing duty to supplement).

Third and relatedly, the road or highway construction that
Caltrans has proposed here seems likely to provide new data
on the effects of construction on old-growth redwoods.
Given that much of the scientific evidence in the record is
non-quantitative and dated, I would expect that such data
would prove important to future decisions surrounding these
historic trees, and—if that data becomes available during the
project—to any decision concerning the preparation of a
supplemental EA or EIS.

So therefore, I respectfully concur, with slight
reservations in these tumultuous times.

1
https://tinyurl.com/y39s2g6o (last visited Nov. 24, 2020).