FOR PUBLICATION

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

BESS BAIR; TRISHA LEE LOTUS;

JEFFREY HEDIN; DAVID SPREEN;

CENTER FOR BIOLOGICAL

DIVERSITY; ENVIRONMENTAL

PROTECTION INFORMATION CENTER;

CALIFORNIANS FOR ALTERNATIVES

TO TOXICS; FRIENDS OF DEL NORTE,

Plaintiffs-Appellees,

v.

CALIFORNIA DEPARTMENT OF

TRANSPORTATION; TOKS

OMISHAKIN, in his capacity as

Director of the California

Department of Transportation,

Defendants-Appellants.

No. 19-16478

D.C. No.

3:17-cv-06419-

WHA

OPINION

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 20105and

2014,6each 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 oldgrowth 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 Revalidation 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 FONSI7in 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 oldgrowth 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 2017,8again 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,9a

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,10a

violation of the Administrative Procedure Act (APA),11a

declaration that Caltrans is responsible for Bair’s attorney’s

fees and costs,12and 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,21and 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 overwhelmtheir 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-TheSea 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,25and 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 thanCalifornia Legal trucks because their tractor units

“are bigger and heavier,”27it 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 offtracking 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).