FOR PUBLICATION

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

HELPING HAND TOOLS; ROB

SIMPSON,

Petitioners,

v.

U.S. ENVIRONMENTAL PROTECTION

AGENCY; GINA MCCARTHY, in her

capacity as Administrator of the U.S.

Environmental Protection Agency;

DEBORAH JORDAN, in her capacity as

Director of the Air Division of U.S.

Environmental Protection Agency

Region IX,

Respondents,

SIERRA PACIFIC INDUSTRIES, INC.,

Respondent-Intervenor.

No. 14-72553
2 HELPING HAND TOOLS V. USEPA

CENTER FOR BIOLOGICAL

DIVERSITY,

Petitioner,

v.

U.S. ENVIRONMENTAL PROTECTION

AGENCY; GINA MCCARTHY, in her

official capacity as Administrator of

the United States Environmental

Protection Agency; JARED

BLUMENFELD, in his official capacity

as Regional Administrator of Region

9 of the United States Environmental

Protection Agency; DEBORAH

JORDAN, in her official capacity as

Director of the Air Division of

Region 9 of the United States

Environmental Protection Agency,

Respondents,

SIERRA PACIFIC INDUSTRIES, INC.,

Respondent-Intervenor.

No. 14-72602

EPA No.

EPA-R09-OAR2012-0634

ORDER AND

AMENDED

OPINION

On Petitions for Review of an Order of the

United States Environmental Protection Agency

Argued and Submitted July 19, 2016

San Francisco, California

Filed September 2, 2016

Amended December 23, 2016
HELPING HAND TOOLS V. USEPA 3

Before: Susan P. Graber and Richard C. Tallman, Circuit

Judges, and Nancy G. Edmunds,* Senior District Judge.

Opinion by Judge Tallman

SUMMARY**

Environmental Law

The panel denied a petition for review of a decision of the

United States Environmental Protection Agency granting

Sierra Pacific Industries, Inc. a prevention of significant

deterioration permit for construction of a new biomassburning power plant at its lumber mill in California.

The panel held that the EPA did not act arbitrarily or

capriciously in granting a prevention of significant

deterioration permit to Sierra Pacific.

Addressing petitioner Helping Hands Tools’ claims that

the EPA was required to consider solar power and a greater

natural gas mix as clean fuel control technologies in the best

available control technology (“BACT”) analysis for

pollutants subject to Clean Air Act regulation, the panel held

that because the EPA properly took the requisite hard look at

Sierra Pacific’s proposed design and the key purpose of

* The Honorable Nancy G. Edmunds, Senior United States District

Judge for the Eastern District of Michigan, sitting by designation.

** This summary constitutes no part of the opinion of the court. It has

been prepared by court staff for the convenience of the reader.
4 HELPING HAND TOOLS V. USEPA

burning its own biomass waste, the EPA reasonably

concluded that consideration of solar or increased natural gas

would disrupt that purpose and redefine the source.

Addressing petitioner Center for Biological Diversity’s

claims raised in response to the supplemental greenhouse gas

BACT analysis, the panel deferred to the agency’s

determination because EPA was largely relying on its own

guidance, acting at the frontiers of science.

COUNSEL

Kevin P. Bundy (argued), San Francisco, California; Brendan

R. Cummings, Joshua Tree, California; Anna Moritz,

Woodinville, Washington; as and for Petitioner Center for

Biological Diversity.

Andrew S. Kingdale (argued), Law Office of Andrew S.

Kingdale, San Francisco, California, for Petitioners Helping

Hand Tools and Robert Simpson.

Dustin J. Maghamfar (argued); John C. Cruden, Assistant

Attorney General; Environmental Defense Section,

Environment & Natural Resources Division, Washington,

D.C.; Brian Doster, Mark Kataoka, Nora Greenglass, and

John Krallman, United States EPA, Office of General

Counsel, Washington, D.C.; Kara Christenson, United States

EPA, Region IX, Office of Regional Counsel, San Francisco,

California; for Respondents.

Joseph R. Palmore (argued), Marc A. Hearron, and Lena

Hughes, Morrison & Foerster LLP, Washington, D.C.;
HELPING HAND TOOLS V. USEPA 5

William M. Sloan, Morrison & Foerster LLP, San Francisco,

California; for Respondent-Intervenor.

Roger R. Martella, Jr., Joel F. Visser, and James R.

Wedeking, Sidley Austin LLP, Washington, D.C., for Amici

Curiae American Wood Counsel and National Alliance of

Forest Owners.

ORDER

The opinion filed on September 2, 2016, is amended as

follows:

1. On page 28 of the slip opinion, “The environmental

impact report (“EIR”) prepared by EPA . . .” is changed to,

“The environmental impact report (“EIR”) prepared by a

consultant for the Shasta County Department of Resource

Management . . .”

2. On page 28 of the slip opinion, “EPA therefore

conducted the EIR assuming . . .” is changed to, “The

consultant therefore conducted the EIR assuming . . .”

3. On page 30 of the slip opinion, “The Bioenergy BACT

Guidance EPA applied to the greenhouse gas emissions from

Sierra Pacific’s new facility is rational and thoroughly

consistent with EPA’s prior guidance” is changed to, “The

Bioenergy BACT Guidance, as applied by EPA to the

greenhouse gas emissions from Sierra Pacific’s new facility,

is rational and is consistent with EPA’s prior practice.”

With these amendments, the panel has voted to deny

Center for Biological Diversity’s petition for panel rehearing.
6 HELPING HAND TOOLS V. USEPA

Judges Graber and Tallman have voted to deny Helping

Hand Tools’ petition for rehearing en banc and Judge

Edmunds so recommends.

The full court has been advised of Helping Hand Tools’

petition for rehearing en banc and no judge has requested a

vote on whether to rehear the matter en banc. Fed. R. App. P.

35.

The petition for panel rehearing and the petition for

rehearing en banc are DENIED. No further petitions for

panel rehearing or rehearing en banc will be entertained.

IT IS SO ORDERED.

OPINION

TALLMAN, Circuit Judge:

Helping Hand Tools (“Helping Hand”) and Center for

Biological Diversity (“Center”) petition for review of a final

decision of the United States Environmental Protection

Agency (“EPA”) granting Sierra Pacific Industries (“Sierra

Pacific”) a prevention of significant deterioration (“PSD”)

permit for construction of a new biomass-burning power plant

at its lumber mill in California. Plaintiffs contend that EPA

issued the PSD permit in violation of the Clean Air Act,

42 U.S.C. §§ 7401–7671q. This is the first time we have

reviewed EPA’s doctrine of “redefining the source.” It also

appears to be the first time that EPA’s framework for

evaluating the best available control technology for

greenhouse gas emissions from facilities burning biomass
HELPING HAND TOOLS V. USEPA 7

fuels is considered by any circuit in the United States. We

hold that EPA did not act arbitrarily or capriciously in

granting a PSD permit to Sierra Pacific pursuant to that

framework.

I

Sierra Pacific owns and operates a lumber manufacturing

facility in Anderson, California, situated at the northern end

of the Central Valley in Shasta County. On March 29, 2010,

Sierra Pacific filed an application for a PSD permit with EPA

in order to construct a new cogeneration1unit at its mill. The

new unit was designed to burn biomass fuels2

in a boiler to

produce steam used to turn turbine blades to generate 31

megawatts of electricity and to heat existing lumber dry kilns. 

Fuel for the unit would come primarily from wood wastes

from Sierra Pacific’s own lumber mills, as well as other

readily available sources of agricultural and urban wood

wastes. The new boiler replaces a smaller existing boiler at

the Anderson Facility. The smaller boiler could burn only

60,000 bone-dry tons (“BDT”)3of the 160,000 BDT of wood

waste the Anderson Facility annually produces. The new

1 Cogeneration units produce both electrical power and heat. See, e.g.,

In re N. Mich. Univ. Ripley Heating Plant, 14 E.A.D. 283, 285 (E.A.B.

2009).

2 Used interchangeably with the terms “bioenergy” and “biogenic,”

biomass fuels include wood waste such as chips and bark from sawmill

operations, forest residue, agricultural residue, crops, grasses, standing

trees, and waste from landfills or water treatment. 76 Fed. Reg. 43,490-

01, 43,493 (July 20, 2011).

3 A BDT is 2,000 pounds of wood pulp with a zero percent moisture

content.
8 HELPING HAND TOOLS V. USEPA

boiler has the increased capacity to burn up to 219,000 BDT

of wood waste. Additionally, the boiler will utilize natural

gas for the limited purpose of startup, shutdown, and flame

stabilization.4

To understand the process by which Sierra Pacific sought

approval by EPA to build the new boiler and the resulting

litigation that ensued first requires an examination of the

statutory and regulatory framework underlying the permitting

process and then an examination of how EPA employed that

process with Sierra Pacific’s particular permit application.

A

The Clean Air Act establishes a comprehensive program

for controlling and improving air quality. As part of this

program, 42 U.S.C. §§ 7470–7479 require new and modified

major emitting facilities, like Sierra Pacific’s new boiler, to

seek a PSD permit prior to construction. Id. § 7475(a). 

These permits are required in geographical regions designated

to meet particular national ambient air quality standards. Id.

§ 7471. Critically, in order to obtain a PSD permit, the

applicant must demonstrate that the proposed facility utilizes

the best available control technology (“BACT”) for every

pollutant subject to regulation by the Clean Air Act. Id.

§ 7475(a)(4). BACT is defined as

4 Flame stabilization is necessary when optimal operations of the boiler

are upset by fuel variability, such as from burning wet wood waste fuel. 

At these times, the optimal combustion of the wood waste is not occurring

and natural gas is used to stabilize combustion and to maximize efficiency

by returning the boiler to desired high temperature operations.
HELPING HAND TOOLS V. USEPA 9

an emission limitation based on the maximum

degree of reduction of each pollutant subject

to regulation . . . from any major emitting

facility, which [EPA], on a case-by-case basis,

. . . determines is achievable for such facility

through application of production processes

and available methods, systems, and

techniques, including fuel cleaning, clean

fuels, or treatment or innovative fuel

combustion techniques for control of each

such pollutant.

Id. § 7479(3). In every case-by-case analysis, EPA will

consider “energy, environmental, and economic impacts and

other costs.” Id.

In 1990, in the absence of any clear guidance from

Congress on how to evaluate BACT for a particular pollutant,

EPA developed a five-step, “top-down” approach. See

Environmental Protection Agency, New Source Review

Workshop Manual, Chapter B (1990) (hereinafter “NSR

Manual”). PSD permit applicants must engage in this

analysis for every regulated pollutant with a significant

emissions increase. Id. at B.4.

Briefly, the top-down analysis begins at Step 1 when the

applicant lists all available control technologies. Id. at B.5. 

Control technologies are those technologies that have “a

practical potential for application to the emissions unit and

the regulated pollutant under evaluation.” Id. This list is

meant to be comprehensive and include all options applicable

to the particular pollutant even though the option may be

eliminated in later steps. Id. at B.5–7. At Step 2, the

applicant eliminates any technically infeasible options and
10 HELPING HAND TOOLS V. USEPA

must clearly document why the particular control option

cannot be used. Id. at B.7. At Step 3, the applicant ranks the

remaining control options against each other in order of

overall effectiveness. Id. at B.7–8. Then, based on this

ranking, at Step 4, the applicant evaluates each control option

to consider the energy, environmental, and economic impacts. 

Id. at B.8. If the top candidate is unfavorable for any of these

reasons, then the applicant evaluates the impacts of the next

available control option. Id. at B.8–9. The most effective

control option that is not eliminated at Step 4 is then chosen

as BACT at Step 5. Id. at B.9.

EPA supplemented the top-down approach as it applied

to greenhouse gases5in March 2011 when it issued new

guidance.6See Environmental Protection Agency, PSD and

Title V Permitting Guidance for Greenhouse Gases (2011)

(hereinafter “GHG Permitting Guidance”). At the same time,

EPA issued more specific BACT guidance for carbon dioxide

emissions from facilities that use biomass as a primary fuel

source. See Environmental Protection Agency, Guidance for

Determining Best Available Control Technology for

Reducing Carbon Dioxide Emissions from Bioenergy

5

“Greenhouse gases” are considered a single pollutant comprised of the

aggregate of carbon dioxide, nitrous oxide, methane, hydrofluorocarbons,

perfluorocarbons, and sulfur hexafluoride.

6 Though the extent to which EPA can require particular facilities to

comply with BACT requirements for greenhouse gases has been heavily

litigated, the Supreme Court recently held that “EPA’s decision to require

BACT for greenhouse gases emitted by sources otherwise subject to PSD

review is” permissible. Util. Air Regulatory Grp. v. EPA, 134 S. Ct. 2427,

2448 (2014). The cogeneration power plant proposed by Sierra Pacific is

such a facility and neither party disputes EPA’s authority to regulate

greenhouse gas emissions from that facility.
HELPING HAND TOOLS V. USEPA 11

Production (2011) (hereinafter “Bioenergy BACT

Guidance”). The Bioenergy BACT Guidance describes how

each step of the five-step BACT analysis should be

approached when a facility proposes to use mostly biomass

as a fuel. Id. at 10–11. It does not supersede prior guidance,

id. at 4, and agencies must still consider each PSD application

on a case-by-case basis, id. at 5.

EPA promulgated a more particular BACT framework

because carbon dioxide emissions from biomass fuels

participate in the carbon cycle differently than other fuels,

and biomass fuel stocks replenish more quickly than fossil

fuel stocks. Id. at 6. Trees are a classic example of this

phenomenon in nature. The short regenerative time means

that new growing plant matter, biomass carbon stocks, can

absorb excess carbon dioxide from the atmosphere more

quickly than fossil fuel carbon stocks. Id. Additionally,

photosynthesis from a well-managed biomass carbon stock,

such as a well-managed forest, can act as a carbon sink,

thereby decreasing the net carbon dioxide released from

burning biomass as fuels. Id. “Biogenic [carbon dioxide]

emissions are distinct from other regulated pollutants at

bioenergy facilities because, unlike other pollutants and other

[greenhouse gases], [carbon dioxide] emissions can

participate directly in the global carbon cycle through

photosynthesis.” Id. at 7. Therefore, EPA modified the steps

of the traditional BACT analysis in particular ways to account

for the unique properties of biomass.

Of particular relevance, at Step 1, EPA notes that “it will

be important to address the extent to which the BACT

analysis for [greenhouse gases] should include” an evaluation

of other fuel types. Id. at 15. However, if utilization of

biomass is the primary purpose of the project, then the agency
12 HELPING HAND TOOLS V. USEPA

can rely on that purpose to determine that another fuel would

redefine the project. Id. If a facility relies primarily on

biomass as fuel, the options at Step 1 “may be limited to (1)

utilization of biomass fuel alone, (2) energy efficiency

improvements, and (3) carbon capture and sequestration.” Id.

Skipping to Step 4,7

the Bioenergy BACT Guidance notes

that the traditional Step 4 analysis is “an environmental,

economic, and energy impacts analysis that includes both

direct and indirect (i.e., collateral) considerations.” Id. at 18. 

EPA emphasizes that indirect environmental impacts and

benefits are better suited to analysis in Step 4, id. at 21, and

burning different biomass fuel stocks will not have a

differential impact on emissions at the facility but at the

forest or region where the biomass fuel is taken, id. at 22.8

7 Steps 2 and 3 are conducted in the same manner as promulgated in the

NSR Manual. Bioenergy BACT Guidance at 16–17.

8 To illustrate the point, burning a dead tree that has fallen in the forest,

instead of a live tree, will have a different impact on the environment. 

Burning the dead tree releases the same amount of carbon dioxide into the

atmosphere that would be released anyway as the tree decomposed. But

the emissions occur faster and at the facility, not in the forest. Burning the

live tree, which uses carbon dioxide for photosynthesis, removes a carbon

dioxide absorbing source from the forest and also releases carbon dioxide

emissions at the facility. The facility emits carbon dioxide in either case

but the environmental impact at the forest—the benefit of removing a

carbon dioxide emitting decomposing tree or the harm in removing a

carbon dioxide absorbing live one—are an indirect result of burning

biomass fuel at the facility. However, a comparison of different biomass

fuel stocks, such as comparing the effects of burning mill waste to the

effects of burning a dead tree, is a much more technical endeavor that

EPA is actively trying to calculate at present. Bioenergy BACT Guidance

at 23. The problem, according to the agency, is the current inability of the

available science to quantify the tradeoff. Id. Where the agency is acting

on the frontiers of developing science, our deference is at its highest level. 
HELPING HAND TOOLS V. USEPA 13

In holding that facilities like Sierra Pacific’s were subject

to PSD permit requirements for greenhouse gas emissions,

the Supreme Court expressly refrained fromdeciding whether

to approve or endorse EPA’s current approach for

determining BACT for greenhouse gases. Util. Air

Regulatory Grp. v. EPA, 134 S. Ct. 2427, 2449 (2014). To

our knowledge, no other court has evaluated EPA’s approach. 

We examine it here as it was used to grant Sierra Pacific its

PSD permit.

B

EPA’s consideration of Sierra Pacific’s permit application

took place in two phases. During the first phase in September

2012, EPA proposed to issue a PSD permit to Sierra Pacific

that required the use of add-on control technologies and

inherently lower-emitting controls as BACTfor the pollutants

analyzed. EPA did not consider BACT for greenhouse gases

because it was not then required.9 EPA accepted Sierra

Pacific’s cap on natural gas use of no more than 10% of the

total fuel required, because it was to be used only for limited

purposes during startup, shutdown, and flame stabilization.

After public comment, EPA issued the PSD permit, and

Helping Hand petitioned the Environmental Appeals Board

(“the Board”) for review. On July 18, 2013, the Board

Baltimore Gas & Elec. Co. v. Nat. Res. Def. Council, Inc., 462 U.S. 87,

103 (1983).

9 At the time, EPA had issued a rule deferring regulation of biogenic

carbon sources in order to examine the science behind biogenic carbon

dioxide emissions from stationary sources like power plants. See Ctr. for

Biological Diversity v. EPA, 722 F.3d 401, 407 (D.C. Cir. 2013). The

District of Columbia Circuit later vacated this rule. Id. at 412.
14 HELPING HAND TOOLS V. USEPA

remanded the PSD permit to EPA for further proceedings on

a single ground—that EPA had abused its discretion in not

holding a public hearing. The Board held that EPA did not

abuse its discretion in approving the permit on all other

issues, two of which are relevant to the current petition before

us.

First, the Board held that EPA did not abuse its discretion

by declining to consider the inclusion of solar power as a fuel

source or a greater percentage of natural gas because it would

impermissibly redefine the source. In making this

determination, the Board reviewed the administrative record

and determined that the primary purpose of the project was to

allow Sierra Pacific “to put to use the hundreds of thousands

of bone-dry tons of wood waste the company has in the

Shasta County region, for the production of lumber and

electricity.” The Board then held that “requiring [Sierra

Pacific] to burn fewer tons of wood waste so that it could

generate solar power or burn more natural gas instead would

plainly disrupt the project’s ‘basic business purpose’ of using

as much surplus biomass as possible” to get rid of the

byproduct and to generate steam to dry lumber in kilns and

produce electricity for use on site and for sale to the electrical

grid.

Second, the Board held that EPA did not abuse its

discretion in limiting the mix of fuel to 90% biomass and

10% natural gas. The Board held that Sierra Pacific’s prudent

use of natural gas for startup, shutdown, and flame

stabilization was a valid reason to limit the quantity of natural

gas used and “not evidence of a project design ‘derived for

reasons of air quality permitting.’”
HELPING HAND TOOLS V. USEPA 15

The second phase of consideration occurred when, just a

few days before the Board’s decision, the District of

Columbia Circuit vacated EPA’s rule deferring BACT

determinations for greenhouse gases emitted from facilities

like Sierra Pacific’s boiler. See Ctr. for Biological Diversity

v. EPA, 722 F.3d 401, 412 (D.C. Cir. 2013). As a result, EPA

conducted a supplemental BACT analysis on Sierra Pacific’s

new biomass facility. EPA considered public comments on

the supplemental analysis, and the Center contended that EPA

could not consider the burning of biomass fuel alone as a

control option at Step 1 and should have directly compared

the environmental impacts of different biomass fuel stocks at

Step 1.

EPA nonetheless issued a final PSD permit notice on

April 25, 2014. The Center appealed to the Board and the

Board dismissed for lack of jurisdiction because, in its July

2013 decision, the Board specifically stated that, pursuant to

40 C.F.R. § 124.19(l)(2)(iii), it would not require or accept an

appeal after the remand. Helping Hand and the Center then

filed the petitions for review now before us. Because all

available administrative remedies have been exhausted, we

have jurisdiction under 42 U.S.C. § 7607(b)(1).10

10 Though not disputed by EPA, because this is the first time the case is

before an Article III court, Helping Hand and the Center must establish

standing. See Sierra Club v. EPA, 762 F.3d 971, 976 (9th Cir. 2014). We

are satisfied that, through the declarations of its members, both Helping

Hand and the Center have associational standing to bring the current

petition. See id. at 976–78 (discussing that “[a]n association has standing

to bring suit on behalf of its members when its members would otherwise

have standing to sue in their own right” and further discussing the factors

demonstrating that the individual members had standing to pursue Clean

Air Act claims (internal quotation marks omitted)).
16 HELPING HAND TOOLS V. USEPA

II

EPA’s decision is reviewed under the Administrative

Procedure Act and may be set aside only if it is “arbitrary,

capricious, an abuse of discretion, or otherwise not in

accordance with law.” 5 U.S.C. § 706(2)(A); see Alaska

Dep’t of Envtl. Conservation v. EPA, 540 U.S. 461, 496–97

(2004). EPA must “articulate[] a rational connection between

the facts found and the choice made.” Sierra Club v. EPA,

346 F.3d 955, 961 (9th Cir. 2003) (alteration in original)

(quoting Ariz. Cattle Growers’ Ass’n v. U.S. Fish & Wildlife,

273 F.3d 1229, 1236 (9th Cir. 2001)).

“[W]e do not simply review whether it was arbitrary or

capricious” for the Board to reject a petitioner’s claims that

EPA clearly erred. Citizens for Clean Air v. EPA, 959 F.2d

839, 845–46 (9th Cir. 1992). “Rather, we conduct a

deferential review of the entire agency action,” including

whether approval of the PSD permit is based on a clearly

erroneous finding of fact or conclusion of law. Id. at 846.

III

First, we address the claims raised by Helping Hand that

EPA was required to consider solar power and a greater

natural gas mix as clean fuel control technologies in the

BACT analysis. This is an issue of first impression in our

circuit, but our opinion is guided by well-reasoned decisions

of the Board and the Seventh Circuit. Because EPA properly

took the requisite hard look at Sierra Pacific’s proposed

design and the key purpose of burning its own biomass waste,

we hold that EPA reasonably concluded that consideration of

solar or increased natural gas would disrupt that purpose and

redefine the source.
HELPING HAND TOOLS V. USEPA 17

A

Though failure to consider all available control

alternatives in a BACT analysis constitutes clear error, EPA

does not have to consider control alternatives that would

“redefine the source.” See, e.g., In re Desert Rock Energy

Co., 14 E.A.D. 484, 526 (E.A.B. 2009); see also NSR Manual

at B.13. In essence, a control alternative redefines the source

if it requires a complete redesign of the facility. In a classic

and simple example, a coal-burning power plant need not

consider a nuclear fuel option as a “cleaner” fuel because it

would require a complete redesign of the coal-burning powerplant. See Sierra Club v. EPA, 499 F.3d 653, 655 (7th Cir.

2007). Considering control technologies is rarely so simple,

however, and EPA engages in a two-step process to

determine whether a control technology will redefine the

source.

First, “the permit applicant initiates the process and . . .

defines the proposed facility’s end, object, aim or

purpose—that is the facility’s basic design.” In re Prairie

State Generating Co., 13 E.A.D. 1, 22 (E.A.B. 2006), aff’d

sub nom Sierra Club, 499 F.3d 653; accord Desert Rock, 14

E.A.D. at 530; In re N. Mich. Univ. Ripley Heating Plant, 14

E.A.D. 283, 301–02 (E.A.B. 2009) (hereinafter “NMU”). 

The purpose must be “objectively discernable.” Prairie State,

13 E.A.D. at 22. Additionally, the applicant’s proposed

definition “must be for reasons independent of air permitting”

and cannot be motivated by cost savings or avoidance of

risks. Id. at 23 n.23; see also Desert Rock, 14 E.A.D. at 530;

NMU, 14 E.A.D. at 302 n.28.

Second, EPA takes a “hard look” at the proposed

definition to determine which design elements are inherent to
18 HELPING HAND TOOLS V. USEPA

the applicant’s purpose and which elements can be changed

to reduce pollutant emissions without disrupting the

applicant’s basic business purpose. Desert Rock, 14 E.A.D.

at 530 (remanding a permit back to the agency because it

failed to take a “hard look” when the agency determined a

particular technology would redefine the source even though

the applicant had considered the technology in its

application); see also Prairie State, 13 E.A.D. at 25–26;

NMU, 14 E.A.D. at 302. This determination and “[r]efining

[of] the statutory definition of ‘control technology’ . . . to

exclude redesign is the kind of judgement by an

administrative agency to which a reviewing court should

defer.” Sierra Club, 499 F.3d at 655. Our examination of

this two-step process for Sierra Pacific’s PSD permit is

guided significantly by the reasoning of our sister circuit in

Sierra Club in which it denied the petition arising from

Prairie State.

When a fuel source is co-located with a facility, EPA

need not consider in the BACT analysis fuel sources that are

not readily available, because it would redefine the source. 

Prairie State, 13 E.A.D. at 28. In Prairie State, Prairie State

Generating Company filed an application for a PSD permit

with EPA to build a coal-burning electrical plant in southern

Illinois. Id. at 4–5. The proposed facility was a “minemouth” plant in which the plant is located at the site of the

coal mine which fuels it. Id. at 16. However, the mine only

produced high-sulfur coal, which emits more sulfur dioxide

pollution than low-sulfur coal from other outlying mines. Id.

at 15. EPA did not list low-sulfur coal as a control

technology in Step 1 of the BACT analysis, however, because

low-sulfur coal would have to be shipped in by rail from long

distances. Id. EPA explained that “it would be inconsistent
HELPING HAND TOOLS V. USEPA 19

with the scope of the project to use coal from other regions of

the country.” Id. at 16.

In making this determination, EPA noted that “the project

that must be addressed when evaluating BACT is the project

for which an application has been submitted.” Id. In this

instance, the construction of a “mine-mouth” plant. Id. EPA

found that “use of a particular coal supply is an inherent

aspect of the proposed project.” Id. EPA broadly considered

alternative coal supplies but rejected a more detailed analysis

because it was beyond the scope of the project. Id. at 18.

The ultimate dispute before the Board lay in determining

how to define the basic purpose of the project and whether

Prairie State could include use of coal from a particular

source as part of that purpose. Id. at 21–22. “The permit

issuer must be mindful that BACT, in most cases, should not

be applied to regulate the applicant’s objective or purpose for

the proposed facility.” Id. at 23. The Board specifically

rejected petitioners’ assertion that the facility’s business

purpose must be viewed broadly as the production of

electricity from coal because “we have frequently recognized

that an electric generating facility’s purpose may be more

narrowly defined.” Id. at 25. The Board held that, in

defining the scope of a project, EPA could consider if a

particular fuel source was an inherent part of the project

design. See id. (“It has also been long-standing EPA policy

that certain fuel choices are integral to the electric power

generating station’s basic design.” (citing NSR Manual at

B.13)).

Additionally, the Board rejected the petitioners’ argument

that a purpose that includes a particular fuel source “would

allow a permit applicant to avoid all BACT review by
20 HELPING HAND TOOLS V. USEPA

including its preferred fuel . . . and hide behind the claim that

requiring anything different would unlawfully ‘redefine’ the

proposed source.” Id. at 27. Because Prairie State could

narrowly define its purpose as burning a particular fuel

source, EPA needed only to review the facility proposed, and

that meant reviewing a facility that burned co-localized highsulfur coal. The Board examined EPA’s review of the

proposed facility and was satisfied that EPA had taken a hard

look at whether further emissions reductions were possible. 

Id. Therefore, the Board concluded, EPA did not err when it

“determined that consideration of low-sulfur coal, because it

necessarily involves a fuel source other than the co-located

mine, would require Prairie State to redefine the fundamental

purpose or basic design of its proposed Facility” and, as a

result, EPA properly rejected low-sulfur fuel from Step 1 of

the BACT analysis. Id. at 28.

In denying the petition arising out of Prairie State, the

Seventh Circuit noted that the Board and EPA were

struggling to draw the line between where “control

technology ends and redesign of the ‘proposed facility’

begins.” Sierra Club, 499 F.3d at 655. The court noted that

if EPA had to consider all clean fuels, it would be required to

consider a nuclear plant rather than a coal-fired one, and it

was clearly not required to do that. See id. (“That approach

would invite a litigation strategy that would make seeking a

permit for a new power plant a Sisyphean labor, for there

would always be one more option to consider.”). Because it

was not as clear cut, the Seventh Circuit characterized its case

as lying on the borderline between control technology and

redesign. Id. at 656.

That borderline, defining the distinction between

considering alternative fuels to be control technologies or to
HELPING HAND TOOLS V. USEPA 21

redefine the facility, is a product of EPA’s framework for

evaluating BACT. The Seventh Circuit therefore held that “it

makes sense to let the EPA, the author of the underlying

distinction, draw it, within reason.” Id. at 655. In the facility

proposed in Sierra Club, the court noted that, in isolation, the

difference between low-sulfur and high-sulfur coal as a fuel

source is a difference in control technology. Id. at 657. But

“the difference between a plant co-located with a coal mine

and a plant that obtains its coal from afar” is a difference in

design. Id. Therefore, the Seventh Circuit upheld the BACT

determination because EPA reasonably drewthe line between

control technology and redefining the source. Id.

The reasoning of Prairie State and Sierra Club has been

applied to subsequent cases from the Board. In NMU,

relating to the construction of a power plant on a college

campus, the Board remanded a PSD permit back to the

agency when it rejected the assertion that considering a

different proportion of a coal and wood fuel mix would

impermissibly redefine the source. 14 E.A.D. at 301–03. 

Particularly, the Board noted that NMU locked onto a

particular fuel combination without any logic or data to

justify the choice. Id. at 303; see also id. at 297 (“[A]lthough

the record reflects that other coal . . . will produce the lowest

sulfur emissions, [the agency] proceeds without explaining

why these sources are unavailable or not technologically

feasible.”). Notably relevant to the current appeal, NMU did

not fully analyze the possibility of natural gas as a fuel source

when the permit application stated that it would be used for

boiler startup and as a backup fuel source. Id. at 297 n.17;

see also In re Cash Creek Generation LLC, 2009 WL

7513857 (E.P.A. 2009) (remanding the permit to the

applicant because the record was insufficient to justify a

determination that an exclusive use of natural gas, a
22 HELPING HAND TOOLS V. USEPA

secondary fuel for the project, would impermissibly redefine

the source).

B

Adopting the two-step analysis promulgated by the Board

and approved by the Seventh Circuit, we must now determine

whether EPA erred in determining that using solar power or

a greater natural gas mix in Sierra Pacific’s proposed facility

would impermissibly redefine the source.

First, we look at how Sierra Pacific itself defined its

facility. In its application description, Sierra Pacific

explicitly stated that it intended to build a power plant “that

would burn biomass fuels in a boiler to produce steam that

would be used to generate electricity and to heat existing

lumber dry kilns at the facility.” Sierra Pacific then went on

to define more particularly that its biomass fuel source would

come from the existing Sierra Pacific mills, in-forest

materials from timberlands owned by Sierra Pacific, and

other readily available sources of agricultural and urban wood

wastes. Sierra Pacific would use natural gas only for the

limited purposes of startup, shutdown, and flame

stabilization. Capped at 10%, Sierra Pacific estimated its

annual usage of natural gas to be significantly below that

limit.

Next, we must determine if EPA took the appropriate

“hard look” at how Sierra Pacific defined the facility and

whether EPA appropriately determined that the burning of

biomass was an inherent element of the facility or whether it

could be changed to reduce emissions. In the PSD permit

issued by EPA, the project description stated that fuel for the

power plant would be generated on-site or received from
HELPING HAND TOOLS V. USEPA 23

other local sources to produce steam in the new facility. The

steam was then to be used to dry lumber and to power a steam

turbine to generate electricity for use onsite or for sale to the

northern California power grid.

Helping Hand argues that the Board improperly deferred

to Sierra Pacific’s purpose of “burning biomass ‘as much as

possible’” and read “clean fuels” out of the Clean Air Act. 

Sierra Pacific’s purpose, according to Helping Hand, is only

to generate steam for lumber drying kilns and to make

electricity. However, Sierra Pacific’s purpose need not be so

limited, see Prairie State, 13 E.A.D. at 25, and Helping Hand

concedes that “Sierra Pacific arguably can have a basic

business purpose of ‘primarily’ burning a dirtier fuel that is

readily available to it.” Just as the Prairie State facility was

co-located with its fuel source, a high-sulfur coal mine, Sierra

Pacific’s facility is co-located with its fuel source, waste from

its lumber manufacturing operations. Therefore, EPA took a

“hard look” at the record and how Sierra Pacific defined its

facility and reasonably determined that use of a co-located

fuel source was an inherent part of the facility’s design.

Having determined that biomass fuel was an inherent part

of the design, we finally examine whether the two proposed

alternative clean fuels were control alternatives that should

have been considered or would impermissibly redefine the

source, keeping in mind the deference EPA must be afforded

in making such a determination. Like the petitioners in

Sierra Club, Helping Hand essentially argues that “if a plant

is capable—with redesign—of burning a clean fuel, it must

undergo a ‘best available control technology’ analysis.” 

499 F.3d at 656. Requiring a solar component just because it

is a cleaner fuel than biomass is the same as requiring Sierra

Pacific to consider the nuclear option. See id. Sierra Pacific
24 HELPING HAND TOOLS V. USEPA

and EPA are not required to take on the “Sisyphean” task of

considering every possible clean fuel alternative. See id. at

655. Therefore, EPA properly dismissed solar as a control

technology.

The Board noted, correctly, that consideration of a greater

natural gas mix was a closer question. Sierra Pacific’s

proposed project falls on the borderline discussed in Sierra

Club. However, unlike the applicant in Sierra Club, Sierra

Pacific is not considering two fuel sources as control options:

one an off-site “clean” fuel, one an on-site “dirty” fuel. In

this instance, Sierra Pacific has access to two on-site fuel

sources: “clean” natural gas and “dirty” biomass. Though

this typically would suggest that Sierra Pacific must consider

a greater mix of natural gas, even when an alternative fuel is

available, it need not be considered at Step 1 if it disrupts the

business purpose. GHG Permitting Guidance at 28

(“[G]reater utilization of a fuel that the applicant is already

proposing to use in some aspect of the project design should

be listed as an option in Step 1 unless it can be demonstrated

that such an option would disrupt the applicant’s basic

business purpose for the proposed facility.”). Here, a greater

use of natural gas would disrupt Sierra Pacific’s intent to burn

the biomass waste it produces from mill operations.11

Notably, unlike the facilities in NMU and Cash Creek,

Sierra Pacific does not propose to use natural gas as a

“secondary” or backup fuel source but only for strictly

limited purposes. And unlike the facilities in NMU and Cash

Creek, Sierra Pacific gave valid reasons for imposing a 10%

11 This conclusion is supported by evidence in the record that Sierra

Pacific produces more waste than could be consumed by the proposed

generator.
HELPING HAND TOOLS V. USEPA 25

cap: that its purpose was to burn as much of its own biomass

waste as possible, and that it expected to burn much less than

10% natural gas because it was being used for such a limited

purpose. Burning natural gas is therefore incidental to Sierra

Pacific’s business purpose of using its on-site source of

biomass as fuel for the new facility. Declining to consider

greater use of an incidental fuel is not arbitrary, capricious, or

an abuse of discretion.12

Drawing the line between control technology and

redefining the source is a technical determination to which a

court should defer to EPA, see Sierra Club, 499 F.3d at 655,

and there was sufficient justification in the record for EPA to

determine that primarily burning biomass from Sierra

Pacific’s own wood waste, a co-localized source, was an

inherent aspect of the facility’s design. Requiring EPA and

Sierra Pacific to consider solar power, a completely different

fuel source, or a greater percentage of natural gas, an

12 Petitioners seize upon Sierra Pacific’s admission that it limited natural

gas to 10% to avoid the nitrous oxide limiting requirements of the New

Source Performance Standards (“NSPS”). See 40 C.F.R. § 60.44b(d). 

Limiting natural gas to avoid a nitrous oxide emission limit is not a design

decision “independent of air permitting.” The Board erroneously held that

such a self-imposed cap was acceptable because it was “federally

enforceable.” Deciding whether or not to impose a cap of 10% natural gas

to avoid NSPS requirements does not exclude consideration of greater

utilization of natural gas in the BACT analysis. See NSR Manual at B.12

(“The only reason for comparing control options to an NSPS is to

determine whether the control option would result in an emissions level

less stringent than the NSPS.”). Though troubling, this error does not

ultimately undermine the key fact that Sierra Pacific’s basic business

purpose and facility design is to use a co-localized source of biomass fuel,

its own wood wastes, to generate steam and electricity for its mill and

limited use of natural gas is incidental to that purpose. For that reason,

any error in justifying the 10% cap is harmless.
26 HELPING HAND TOOLS V. USEPA

incidental fuel source, would redefine the source. EPA did

not act arbitrarily or capriciously and Helping Hand’s petition

is denied.

IV

Next we address the claims raised by the Center in

response to the supplemental greenhouse gas BACT analysis. 

The Center contends that EPA could not consider burning of

biomass fuel alone as a control option at Step 1 and that it

erred in weighing the effects of different biomass fuel stocks

at Step 4 instead of directly comparing them at Step 1. 

Because EPA was largely relying on its own guidance, acting

at the frontiers of science, we defer to the agency’s

determination. See Baltimore Gas & Elec. Co. v. Nat. Res.

Def. Council, Inc., 462 U.S. 87, 103 (1983).

A

We review questions of statutory interpretations of the

Clean Air Act by the two-step process of Chevron U.S.A. Inc.

v. Natural Resources Defense Council, Inc., 467 U.S. 837,

842–43 (1984). See Vigil v. Leavitt, 381 F.3d 826, 833–34

(9th Cir. 2004). If Congress has not directly spoken to the

precise issue, or the statute is silent or ambiguous, the court

must determine if the agency’s construction is permissible. 

Chevron, 467 U.S. at 842–43. When Congress has not

provided clear guidance in a statute, an agency may fill the

gap and its construction is to be given “controlling weight

unless . . . arbitrary, capricious, or manifestly contrary to the

statute.” Id. at 844 (deferring to EPA’s interpretation of

“source” in the Clean Air Act); see also EPA v. EME Homer

City Generation, L.P., 134 S. Ct. 1584, 1603–07 (2014)
HELPING HAND TOOLS V. USEPA 27

(deferring to EPA’s interpretation of “amount” in the Good

Neighbor Provision of the Clean Air Act).

“[T]he weight that we are to give an administrative

interpretation not intended by an agency to carry the general

force of law is a function of that interpretation’s

thoroughness, rational validity, and consistency with prior

and subsequent pronouncements.” Wilderness Soc’y v. U.S.

Fish & Wildlife Serv., 353 F.3d 1051, 1068 (9th Cir. 2003)

(en banc). However, when an agency is acting “within its

area of special expertise, at the frontiers of science,” the court

should “be at its most deferential.” Baltimore Gas & Elec.

Co., 462 U.S. at 103; see also Nat’l Wildlife Fed’n v. U.S.

Army Corps of Eng’rs, 384 F.3d 1163, 1174 (9th Cir. 2004)

(“Where scientific and technical expertise is necessarily

involved in agency decision-making, . . . a reviewing court

must be highly deferential to the judgment of the agency.”).

What level of deference we must show EPA’s BACT

guidance is unclear. The publications are not intended to

carry the force of law because EPA must still analyze each

application on a case-by-case basis. However, all the

publications were promulgated by EPA in order to bring

meaning to the BACT statute which Congress has not defined

any further than it did in 42 U.S.C. § 7479(3). EPA

promulgated these policies specifically to carry out

Congress’s intent. We need not resolve the issue here,

however, because, as discussed below, under either standard

EPA’s actions were neither arbitrary nor capricious.

B

Ultimately, the Center’s concerns are not particular to the

Sierra Pacific permit but attack the Bioenergy BACT
28 HELPING HAND TOOLS V. USEPA

Guidance. The Bioenergy BACT Guidance builds on the

NSR Manual that EPA has used for decades and proposes a

more detailed analysis for a particular pollutant—greenhouse

gas emissions from biomass fuels—because the emissions

from this particular fuel source have unique environmental

consequences. Nothing prohibits EPA from refining its topdown BACT approach for particular pollutants—particularly

when the refinement is heavily dependent upon the agency’s

own scientific expertise. Following the Bioenergy BACT

Guidance is therefore thorough, rational, and consistent with

EPA’s prior practice. See Wilderness Soc’y, 353 F.3d at

1068. And as explained above, we must defer to EPA agency

expertise and not disturb the analysis set forth in the

Bioenergy BACT Guidance.

In particular, the Center contends that utilization of

biomass fuel alone cannot be considered a control technology

for the burning of biomass fuel at Step 1 of the BACT

analysis because it does not “control” biomass emissions. 

EPA argues, however, that the option is used as a baseline to

which all other options are compared and is not inconsistent

with the traditional top-down approach. Moreover, EPA did

not ultimately choose this option but selected other control

technologies including: combustion of specific biomass fuel

stocks; energy efficient design, operation, and maintenance;

and employing good combustion practices and efficient

operation as a cogeneration unit. In the end, EPA chose the

same control measures as five other facilities. Providing a

baseline in the BACT analysis does not make the ultimate

determination arbitrary, capricious, or even unreasonable.

The Center further argues that the effect of burning

different biomass fuel stocks should be considered at Step 1

of the analysis. EPA does not disagree in theory. But EPA
HELPING HAND TOOLS V. USEPA 29

currently lacks the scientific data at this time to make such a

quantitative determination and is actively collecting the data

to do in the future the type of analysis desired by the Center. 

See Bioenergy BACT Guidance at 23. Furthermore, because

the same amount of carbon dioxide will be released at the

facility no matter which biomass fuel stock is burned, any

difference in environmental consequences is indirect. Id. at

22. Therefore, consistent with the NSR Manual, these

indirect environmental impacts and benefits are better suited

to analysis in Step 4.

Acknowledging the differences in the environmental

impact of different biomass fuel stocks, however, EPA

responded to the Center’s comment by clarifying the fuel

restrictions in the final permit. Notably, Sierra Pacific and

EPA were particularly proactive in ensuring the appropriate

fuel restrictions were written into the PSD permit. Sierra

Pacific’s initial application contemplated the use of colocalized mill waste as well as in-forest materials from Sierra

Pacific’s timber operations and other readily available

agricultural and urban wood wastes.

The environmental impact report (“EIR”) prepared by a

consultant for the Shasta County Department of Resource

Management noted that there were different estimates of the

type of biomass fuel blend Sierra Pacific planned on using,

ranging from100% mill wastes to a blend supplementing mill

wastes with biomass from forest-harvesting operations,

forest-thinning operations, agricultural waste from the

Sacramento Valley, and urban wood waste. The consultant

therefore conducted the EIR assuming a “worst-case”

scenario in which 35% of the biomass used was not colocalized with the facility. The supplemental Statement of

Basis and Ambient Air Quality Impact Report also assumed
30 HELPING HAND TOOLS V. USEPA

a biomass fuel mix of 75% mill residue and 25% in-forest

residues, agricultural residues, and urban wood residues.

Based on the EIR, EPA drafted a PSD permit restricting

fuel to “clean cellulosic biomass” allowing Sierra Pacific to

burn an extensive list of biomass fuels at the facility. Sierra

Pacific commented on the draft asking for more restrictive

limitations on the types of biomass fuel it would be allowed

to use in its facility because it was more consistent with the

original application. EPA adopted Sierra Pacific’s

modifications in another draft of the permit, which was then

further modified in response to the Center’s comments.

Though it was not prepared at the time to compare the

environmental impacts of sawmill residue versus other

biomass wastes, EPA ensured that Sierra Pacific would not

log timber solely for the purpose of using it as biomass for

the new facility. EPA limited Sierra Pacific to only the

particular biomass fuels readily available to the facility: mill

residues, untreated wood debris from urban areas such as

pallets and crates, agricultural crops and residues, forest

residues, and non-merchantable forest biomass. The only

trees that can be burned in Sierra Pacific’s facility, therefore,

are those that would be removed from the forest anyway as

part of Sierra Pacific’s ongoing forest management and

forest-thinning operations.

Though the Center argues that EPA is equipped to

proceed with a quantitative analysis of different biomass fuel

stocks at Step 1, EPA says it cannot do that based on the

current state of the science. Because the agency is acting at

the frontiers of science, we must defer. See Baltimore Gas &

Elec., 462 U.S. at 103. The Center does not clearly explain

how EPA’s analysis here is not thorough, rational, and
HELPING HAND TOOLS V. USEPA 31

consistent with EPA’s prior guidance on BACT. Sierra

Pacific is restricted to the forms of biomass waste readily

available to it and cannot clear cut forests just to produce

electricity for its lumber mills. EPA did consider the

environmental impacts of different biomass fuel stocks, just

not in the manner or the level of detail the Center would

prefer. Because we must defer to EPA’s interpretation of

BACT and its scientific expertise, EPA’s analysis is not

arbitrary, capricious, or an abuse of discretion, and we deny

the Center’s petition.

V

Sierra Pacific’s application went through an extensive

process to issue a reasoned PSD permit for its new biomass

burning boiler. EPA properly defined the project and rejected

control technologies that redefined the project with thoughtful

and reasonable explanations. The Bioenergy BACT

Guidance, as applied by EPA to the greenhouse gas emissions

from Sierra Pacific’s new facility, is rational and is consistent

with EPA’s prior practice. The guidance relies extensively on

the continually evolving analysis of the environmental effect

of different biomass fuels in the ever-developing field of

climate-change science. It is not our place to interfere with

EPA’s expertise when the record shows that its endeavors

were reasonable.

Costs are awarded to Respondents.

The petitions for review are DENIED.