2542 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

2Sec. 701, Public Law 114–74, 129 Stat. 599–601 

(Bipartisan Budget Act of 2015). 

3See M–21–10, Implementation of Penalty 

Inflation Adjustments for 2021, Pursuant to the 

Federal Civil Penalties Inflation Adjustment Act 

Improvements Act of 2015, https://

www.whitehouse.gov/wp-content/uploads/2020/12/ 

M-21-10.pdf. 

Adjustment of Civil Penalties 

On November 2, 2015, the President 

signed into law the Federal Civil 

Penalties Inflation Adjustment Act 

Improvements Act of 2015,2 which 

requires agencies to adjust civil 

monetary penalties for inflation and to 

publish the adjustments in the Federal 

Register. An initial adjustment was 

required to be made by interim final 

rule published by July 1, 2016, and 

effective by August 1, 2016. Subsequent 

adjustments must be published by 

January 15 each year after 2016. 

On December 23, 2020, the Office of 

Management and Budget issued 

memorandum M–21–10 on 

implementation of the 2021 annual 

inflation adjustment pursuant to the 

2015 Act.3 The memorandum provides 

agencies with the cost-of-living 

adjustment multiplier for 2021, which is 

based on the Consumer Price Index 

(CPI–U) for the month of October 2020, 

not seasonally adjusted. The multiplier 

for 2021 is 1.01182. The adjusted 

maximum amounts are $2,259 for 

section 4071 penalties and $301 for 

section 4302 penalties. 

Compliance With Regulatory 

Requirements 

The Office of Management and Budget 

has determined that this rule is not a 

‘‘significant regulatory action’’ under 

Executive Order 12866 and therefore not 

subject to its review. As this is not a 

significant regulatory action under E.O. 

12866, it is not considered an E.O. 

13771 regulatory action. 

The Office of Management and Budget 

also has determined that notice and 

public comment on this final rule are 

unnecessary because the adjustment of 

civil penalties implemented in the rule 

is required by law. See 5 U.S.C. 553(b). 

Because no general notice of proposed 

rulemaking is required for this rule, the 

Regulatory Flexibility Act of 1980 does 

not apply. See 5 U.S.C. 601(2). 

List of Subjects 

29 CFR Part 4071 

Penalties. 

29 CFR Part 4302 

Penalties. 

In consideration of the foregoing, 

PBGC amends 29 CFR parts 4071 and 

4302 as follows: 

PART 4071—PENALTIES FOR 

FAILURE TO PROVIDE CERTAIN 

NOTICES OR OTHER MATERIAL 

INFORMATION 

■ 1. The authority citation for part 4071 

continues to read as follows: 

Authority: 28 U.S.C. 2461 note, as 

amended by sec. 701, Pub. L. 114–74, 129 

Stat. 599–601; 29 U.S.C. 1302(b)(3), 1371. 

§ 4071.3 [Amended] 

■ 2. In § 4071.3, the figures ‘‘$2,233’’ are 

removed and the figures ‘‘$2,259’’ are 

added in their place. 

PART 4302—PENALTIES FOR 

FAILURE TO PROVIDE CERTAIN 

MULTIEMPLOYER PLAN NOTICES 

■ 3. The authority citation for part 4302 

continues to read as follows: 

Authority: 28 U.S.C. 2461 note, as 

amended by sec. 701, Pub. L. 114–74, 129 

Stat. 599–601; 29 U.S.C. 1302(b)(3), 1452. 

§ 4302.3 [Amended] 

■ 4. In § 4302.3, the figures ‘‘$297’’ are 

removed and the figures ‘‘$301’’ are 

added in their place. 

Issued in Washington, DC, by: 

Gordon Hartogensis, 

Director, Pension Benefit Guaranty 

Corporation. 

[FR Doc. 2021–00297 Filed 1–12–21; 8:45 am] 

BILLING CODE 7709–02–P 

DEPARTMENT OF COMMERCE 

Patent and Trademark Office 

37 CFR Part 1 

[Docket No. PTO–P–2019–0009] 

RIN 0651–AD33 

Small Entity Government Use License 

Exception 

Correction 

In rule document 2020–27049 

appearing on pages 82917–82923 in the 

issue of Monday, December 21, 2020, 

make the following correction: 

On page 82917, in the third column, 

in the DATES section, change ‘‘January 

20, 2021’’ to read ‘‘January 21, 2021.’’ 

[FR Doc. C1–2020–27049 Filed 1–12–21; 8:45 am] 

BILLING CODE 1301–00–D 

DEPARTMENT OF COMMERCE 

Patent and Trademark Office 

37 CFR Part 42 

[Docket No. PTO–P–2019–0011] 

RIN 0651–AD34 

Rules of Practice To Allocate the 

Burden of Persuasion on Motions To 

Amend in Trial Proceedings Before the 

Patent Trial and Appeal Board 

Correction 

In rule document 2020–28159 

appearing on pages 82923–82936 in the 

issue of Monday, December 21, 2020, 

make the following correction: 

(1) On page 82924, in the first 

column, in the DATES section, in the 

second line under the heading, change 

‘‘January 20, 2021’’ to read ‘‘January 21, 

2021.’’ 

(2) On page 82924, in the first 

column, in the DATES section, in the 

sixth line under the heading, change 

‘‘January 20, 2021’’ to read ‘‘January 21, 

2021.’’ 

[FR Doc. C1–2020–28159 Filed 1–12–21; 8:45 am] 

BILLING CODE 1301–00–D 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 60 

[EPA–HQ–OAR–2013–0495; FRL–10019–30– 

OAR] 

RIN 2060–AT56 

Pollutant-Specific Significant 

Contribution Finding for Greenhouse 

Gas Emissions From New, Modified, 

and Reconstructed Stationary 

Sources: Electric Utility Generating 

Units, and Process for Determining 

Significance of Other New Source 

Performance Standards Source 

Categories 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Final rule. 

SUMMARY: In this final action, the U.S. 

Environmental Protection Agency (EPA) 

is finalizing a significant contribution 

finding (SCF) for purposes of regulating 

source categories for greenhouse gas 

(GHG) emissions, under section 111(b) 

of the Clean Air Act (CAA) for electric 

generating units (EGUs), and in doing 

so, reaffirming that EGUs remain a listed 

source category. The EPA has reached 

that conclusion by articulating a 

framework under which source 

categories are considered to contribute 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2543 

significantly to dangerous air pollution 

due to their GHG emissions if the 

amount of those emissions exceeds 3 

percent of total U.S. GHG emissions. 

The EPA is applying the 3-percent 

threshold to the EGU source category to 

demonstrate that GHG emissions from 

the EGU source category would 

contribute significantly to dangerous air 

pollution. While EGU GHG emissions 

exceed this threshold by a sufficient 

magnitude to warrant an SCF without 

more ado, the EPA has also, for 

completeness, analyzed EGU emissions 

under a secondary criteria framework, 

which also demonstrates the propriety 

of the SCF. 

DATES: The final rule is effective on 

March 15, 2021. 

ADDRESSES: The EPA has established a 

docket for this action under Docket ID 

No. EPA–HQ–OAR–2013–0495. All 

documents in the docket are listed on 

the https://www.regulations.gov/ 

website. Although listed, some 

information is not publicly available, 

e.g., Confidential Business Information 

or other information whose disclosure is 

restricted by statute. Certain other 

material, such as copyrighted material, 

is not placed on the internet and will be 

publicly available only in hard copy 

form. With the exception of such 

material, publicly available docket 

materials are available electronically 

through https://www.regulations.gov/. 

Out of an abundance of caution for 

members of the public and our staff, the 

EPA Docket Center and Reading Room 

are closed to the public, with limited 

exceptions, to reduce the risk of 

transmitting COVID–19. Our Docket 

Center staff will continue to provide 

remote customer service via email, 

phone, and webform. For further 

information on EPA Docket Center 

services and the current status, please 

visit us online at https://www.epa.gov/ 

dockets. 

FOR FURTHER INFORMATION CONTACT: For 

questions about this final action, contact 

Mr. Christopher Werner, Sector Policies 

and Programs Division (D243–01), 

Office of Air Quality Planning and 

Standards, U.S. Environmental 

Protection Agency, Research Triangle 

Park, North Carolina 27711; telephone 

number: (919) 541–5133; fax number: 

(919) 541–4991; and email address: 

werner.christopher@epa.gov. 

SUPPLEMENTARY INFORMATION: 

Preamble acronyms and 

abbreviations. The EPA uses multiple 

acronyms and terms in this preamble. 

While this list may not be exhaustive, to 

ease the reading of this preamble and for 

reference purposes, the EPA defines the 

following terms and acronyms here: 

AEO Annual Energy Outlook 

BSER best system of emission reduction 

°C degrees Celsius 

CAA Clean Air Act 

CFR Code of Federal Regulations 

CH4 methane 

CO carbon monoxide 

CO2 carbon dioxide 

D.C. Cir. United States Court of Appeals for 

the District of Columbia Circuit 

DOE Department of Energy 

EGU electric utility generating unit 

EIA U.S. Energy Information 

Administration 

EPA Environmental Protection Agency 

°F degrees Fahrenheit 

GHG greenhouse gas 

HAP hazardous air pollutant(s) 

HFC hydrofluorocarbon 

km kilometers 

M million 

N2O nitrous oxide 

NAICS North American Industry 

Classification System 

NGCC natural gas combined cycle 

NOX nitrogen oxides 

NSPS new source performance standards 

OMB Office of Management and Budget 

PC pulverized coal 

PFC perfluorocarbon 

PM particulate matter 

SF6 sulfur hexafluoride 

SO2 sulfur dioxide 

U.S. United States 

U.S.C. United States Code 

Organization of this document. The 

information in this preamble is 

organized as follows: 

I. General Information 

A. Does this action apply to me? 

B. Where can I get a copy of this document 

and other related information? 

C. Judicial Review 

II. Executive Summary 

A. What is the purpose of this regulatory 

action? 

B. What is the summary of the major 

provisions in this action? 

C. What are the costs and benefits? 

III. Summary of Previous Rulemaking 

Actions 

IV. Pollutant-Specific Significant 

Contribution Finding (SCF) 

A. Background 

B. What is a Significant Contribution 

Finding (SCF)? 

C. Primary Criteria for Determining 

Significance 

D. Secondary Criteria for Determining 

Significance 

E. Significant Contribution Finding for 

EGUs 

V. Summary of Cost, Environmental, and 

Economic Impacts 

A. What are the affected facilities? 

B. What are the air quality impacts? 

C. What are the energy impacts? 

D. What are the cost impacts? 

E. What are the economic impacts? 

F. What are the benefits? 

VI. Statutory and Executive Order Reviews 

A. Executive Order 12866: Regulatory 

Planning and Review and Executive 

Order 13563: Improving Regulation and 

Regulatory Review 

B. Executive Order 13771: Reducing 

Regulations and Controlling Regulatory 

Costs 

C. Paperwork Reduction Act (PRA) 

D. Regulatory Flexibility Act (RFA) 

E. Unfunded Mandates Reform Act 

(UMRA) 

F. Executive Order 13132: Federalism 

G. Executive Order 13175: Consultation 

and Coordination With Indian Tribal 

Governments 

H. Executive Order 13045: Protection of 

Children From Environmental Health 

Risks and Safety Risks 

I. Executive Order 13211: Actions 

Concerning Regulations That 

Significantly Affect Energy Supply, 

Distribution, or Use 

J. National Technology Transfer and 

Advancement Act (NTTAA) 

K. Executive Order 12898: Federal Actions 

To Address Environmental Justice in 

Minority Populations and Low-Income 

Populations 

L. Congressional Review Act (CRA) 

I. General Information 

A. Does this action apply to me? 

Categories and entities potentially 

impacted by this rule include sources 

subject to new source performance 

standards (NSPS) requirements under 

section 111 of the CAA. While this rule 

informs all NSPS source categories, the 

EPA is finalizing a SCF specific to 

electric generating units regulated under 

40 CFR part 60, subpart TTTT. The 

North American Industry Classification 

System (NAICS) code for the industrial, 

federal government, and state/local 

government electric generating units is 

221112. The NAICS code for tribal 

government electric generating units is 

921150. 

B. Where can I get a copy of this 

document and other related 

information? 

In addition to being available in the 

docket, an electronic copy of this final 

action is available on the internet. 

Following signature by the EPA 

Administrator, the EPA will post a copy 

of this final action at https://

www.epa.gov/stationary-sources-airpollution/nsps-ghg-emissions-newmodified-and-reconstructed-electricutility. Following publication in the 

Federal Register, the EPA will post the 

Federal Register version of the final rule 

and key technical documents at this 

same website. 

C. Judicial Review 

Under section 307(b)(1) of the Clean 

Air Act (CAA), judicial review of this 

final rule is available only by filing a 

petition for review in the United States 

Court of Appeals for the District of 

Columbia Circuit (the D.C. Circuit) by 

March 15, 2021. Moreover, under 

2544 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

1Executive Order 13783, Section 1(c), 82 FR 

16093, March 31, 2017. 

2 In the reference case for the most recent Annual 

Energy Outlook (AEO2020), the EIA projected no 

additions of new planned or unplanned coal 

capacity through 2050 (www.eia.gov/aeo2020; Table 

9. Electricity Generating Capacity). 

3Standards developed under the NSPS program 

must, by statutory requirement, be reviewed, at 

least, every 8 years. 

section 307(b)(2) of the CAA, the 

requirements established by this final 

rule may not be challenged separately in 

any civil or criminal proceedings 

brought by the EPA to enforce these 

requirements. The Administrator has 

determined that this action is subject to 

section 307(d) of the CAA (42 U.S.C. 

7607(d)(1)(V)). Section 307(d)(7)(B) of 

the CAA further provides that ‘‘[o]nly an 

objection to a rule or procedure which 

was raised with reasonable specificity 

during the period for public comment 

(including any public hearing) may be 

raised during judicial review.’’ This 

section also provides a mechanism for 

the EPA to convene a proceeding for 

reconsideration ‘‘[i]f the person raising 

an objection can demonstrate to the EPA 

that it was impracticable to raise such 

objection within [the period for public 

comment] or if the grounds for such 

objection arose after the period for 

public comment, (but within the time 

specified for judicial review) and if such 

objection is of central relevance to the 

outcome of the rule.’’ Any person 

seeking to make such a demonstration to 

us should submit a Petition for 

Reconsideration to the Office of the 

Administrator, U.S. Environmental 

Protection Agency, Room 3000, WJC 

South Building, 1200 Pennsylvania Ave. 

NW, Washington, DC 20460, with a 

copy to both the person(s) listed in the 

preceding FOR FURTHER INFORMATION

CONTACT section, and the Associate 

General Counsel for the Air and 

Radiation Law Office, Office of General 

Counsel (Mail Code 2344A), U.S. 

Environmental Protection Agency, 1200 

Pennsylvania Ave. NW, Washington, DC 

20460. 

II. Executive Summary 

A. What is the purpose of this regulatory 

action? 

In Executive Order 13783 (Promoting 

Energy Independence and Economic 

Growth), all executive departments and 

agencies, including the EPA, were 

directed to ‘‘immediately review 

existing regulations that potentially 

burden the development or use of 

domestically produced energy resources 

and appropriately suspend, revise, or 

rescind those that unduly burden the 

development of domestic energy 

resources beyond the degree necessary 

to protect the public interest or 

otherwise comply with the law.’’ 1

Moreover, the Executive Order directed 

the EPA to undertake this process of 

review with regard to the ‘‘Standards of 

Performance for Greenhouse Gas 

Emissions from New, Modified, and 

Reconstructed Stationary Sources: 

Electric Utility Generating Units,’’ 80 FR 

64510 (October 23, 2015) (2015 Rule). 

In a document signed the same day as 

Executive Order 13783 and published in 

the Federal Register at 82 FR 16330 

(April 4, 2017), the EPA announced 

that, consistent with the Executive 

Order, it was initiating a review of the 

2015 Rule and providing notice of a 

forthcoming proposed rulemaking 

consistent with the Executive Order. 

After due deliberation, the EPA issued 

a proposed rulemaking, ‘‘Review of 

Standards of Performance for 

Greenhouse Gas Emissions From New, 

Modified, and Reconstructed Stationary 

Sources: Electric Utility Generating 

Units—Proposed Rule,’’ 83 FR 65424 

(December 20, 2018) (2018 Proposal). 

Here the EPA is finalizing a rulemaking 

with respect to whether GHG emissions 

from EGUs contribute significantly to 

dangerous air pollution, in reliance on 

a methodology articulated herein for 

determining whether GHG emissions 

from other NSPS source categories 

contribute significantly to dangerous air 

pollution. Any action regarding the 

proposal to revise the standards of 

performance, including the underlying 

determinations of the BSER, for new, 

reconstructed, and modified coal-fired 

EGUs, including certain technical 

issues, is beyond the scope of this final 

rule and comments received on the 2018 

Proposal will be addressed in a separate 

future action. 

B. What is the summary of the major 

provisions in this action? 

The EPA is finalizing a pollutantspecific SCF for GHG emissions from 

EGUs. That finding is based on an 

emissions threshold framework for 

determining significance, as well as 

secondary criteria to be applied in 

certain circumstances, for other NSPS 

source categories. 

C. What are the costs and benefits? 

In 2015, the EPA promulgated 

‘‘Standards of Performance for 

Greenhouse Gas Emissions From New, 

Modified, and Reconstructed Stationary 

Sources: Electric Utility Generating 

Units,’’ 80 FR 64510 (October 23, 2015) 

(2015 Rule). When the EPA promulgated 

the 2015 Rule, it took note of both 

utility announcements and U.S. Energy 

Information Administration (EIA) 

modeling and, based on that 

information, concluded that even in the 

absence of this rule, (1) existing and 

anticipated economic conditions are 

such that few, if any, coal-fired EGUs 

will be built in the foreseeable future, 

and that (2) utilities and project 

developers are expected to choose new 

generation technologies (primarily 

natural gas combined cycle (NGCC)) that 

would meet the final standards and also 

renewable generating sources that are 

not affected by these final standards. 

See 80 FR 64515 (October 23, 2015). The 

EPA, therefore, projected that the 2015 

Rule would ‘‘result in negligible CO2

emission changes, quantified benefits, 

and costs by 2022 as a result of the 

performance standards for newly 

constructed EGUs.’’ Id. The Agency 

went on to say that it had been ‘‘notified 

of few power sector new source 

performance standards (NSPS) 

modifications or reconstructions.’’ 

Based on that additional information, 

the EPA said it ‘‘expects that few EGUs 

will trigger either the modification or 

the reconstruction provisions’’ of the 

2015 Rule. Id. at 64516. 

The EPA has concluded that the 

projections described in the 2015 Rule 

remain generally correct.2 In the period 

of analysis,3 the EPA expects there to be 

few, if any, newly constructed, 

reconstructed, or modified sources that 

will trigger the provisions the EPA is 

promulgating in this action. 

Consequently, the EPA projects that 

there will be no significant changes in 

carbon dioxide (CO2) emissions or in 

compliance costs as a result of this final 

rule. 

III. Summary of Previous Rulemaking 

Actions 

On December 20, 2018, the EPA 

published a proposal to revise certain 

parts of the 2015 Rule; ‘‘Review of 

Standards of Performance for 

Greenhouse Gas Emissions From New, 

Modified, and Reconstructed Stationary 

Sources: Electric Utility Generating 

Units.’’ 83 FR 65424 (2018 Proposal). 

The majority of that proposal was 

dedicated to the issue of the best system 

of emission reduction (BSER) for newly 

constructed, modified, and 

reconstructed coal-fired EGUs. 

Comments received on that issue are not 

being addressed in this rule and will be 

addressed in any future EPA action. In 

that proposal, the EPA solicited 

comment on whether to make a 

pollutant-specific significant 

contribution determination for GHG 

emissions from EGUs, 83 FR 65432 n. 

25, which is the subject of this action. 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2545 

4See ‘‘List of Categories of Stationary Sources,’’ 

36 FR 5931 (March 31, 1971) (listing source 

category); ‘‘Standards of Performance for New 

Stationary Sources,’’ 36 FR 24376 (December 31, 

1971) (promulgating NSPS for source category). 

5See ‘‘Standards of Performance for New 

Stationary Sources; Gas Turbines,’’ 44 FR 52792 

(September 10, 1979) (listing and promulgating 

NSPS for source category). 

6See ‘‘Priority List and Additions to the List of 

Categories of Stationary Sources,’’ 49 FR 49222 

(August 21, 1979) (listing source category); 

‘‘Standards of Performance for New Stationary 

Sources; Equipment Leaks of VOC From Onshore 

Natural Gas Processing Plants,’’ 50 FR 26124 (June 

23, 1985), and ‘‘Standards of Performance for New 

Stationary Sources; Onshore Natural Gas Processing 

SO2 Emissions,’’ 50 FR 40160 (October 1, 1985) 

(promulgating standards of performance). 

7Some commenters on the 2018 Proposal also 

said that, in the 2009 Endangerment Finding, the 

EPA specifically defined air pollution, as referred 

to in section 202(a) of the CAA, to be the mix of 

six well-mixed, long-lived, and directly emitted 

GHGs: CO2, CH4, N2O, HFCs, PFCs, and SF6. 74 FR 

66497. They commented that the EPA needs to 

make, but has never made, a separate finding that 

CO2 alone is reasonably anticipated to endanger the 

public health or welfare. The Agency disagrees with 

commenters. The air pollutant that the 2015 Rule 

regulates is GHG, and that air pollutant contributes 

to the same GHG air pollution that was addressed 

by the Endangerment Finding. The standards of 

performance adopted in the 2015 Rule take the form 

of an emission limitation on only one constituent 

gas of this air pollutant, CO2. See 40 CFR 60.5515(a) 

(‘‘The pollutants regulated by this subpart are 

greenhouse gases. The greenhouse gas standard in 

this subpart is in the form of a limitation on 

emission of carbon dioxide.’’). This is reasonable, 

given that CO2 is the constituent gas emitted in the 

largest volume by the source category and for which 

there are available controls that are technically 

feasible and cost effective. There is no requirement 

that standards of performance address each 

component of an air pollutant. CAA section 

111(b)(1)(B) requires the EPA to establish 

‘‘standards of performance’’ for listed source 

categories, and the definition of ‘‘standard of 

performance’’ in CAA section 111(a)(1) does not 

specify which air pollutants must be controlled. 

Moreover, as the EPA noted in the 2015 Rule, the 

information considered in the 2009 Endangerment 

Finding and its supporting record, together with 

additional discussion of GHG impacts in the 2015 

Rule, makes clear that GHG air pollution may 

reasonably be anticipated to endanger public health 

or welfare. See 80 FR 64517, 64530 and 31. Because 

the 2015 Rule followed the same approach as in the 

2009 findings and regulated the same pollutant as 

contributing to the same air pollution (to reiterate, 

both the air pollutant and the air pollution are GHG 

as the group of six well-mixed gases, including 

CO2), it was not necessary to evaluate CO2

separately. The EPA took the same position in the 

2016 Oil & Gas Rule in response to a similar 

comment concerning CH4. See 81 FR 35843. 

IV. Pollutant-Specific Significant 

Contribution Finding (SCF) 

A. Background 

CAA section 111(b)(1)(A) states that 

‘‘[The Administrator] shall include a 

category of sources in such list if in his 

judgment it causes, or contributes 

significantly to, air pollution which may 

reasonably be anticipated to endanger 

public health or welfare.’’ 

In the 2015 Rule, the EPA 

promulgated standards for GHG 

(measured CO2 emissions) from fossil 

fuel-fired steam generating EGUs and 

combustion turbines, a pollutant that 

the Administrator had not considered 

when he listed the categories of those 

sources—fossil fuel-fired steam 

generators 4 and stationary gas 

turbines.5 See 80 FR 64510. Similarly, in 

2016, the EPA promulgated an NSPS for 

GHG (measured by methane (CH4) 

emissions) from oil and gas sources, a 

pollutant that the Administrator had not 

considered when he listed the category 

for those sources—the Crude Oil and 

Natural Gas Production source 

category.6 See 81 FR 35824 (June 3, 

2016) (2016 Oil & Gas Rule). 

In each rule, the EPA interpreted CAA 

section 111(b) to require that an SCF 

and endangerment finding be made only 

with respect to the source category, at 

the time the EPA lists the category, and 

to authorize the EPA to promulgate 

NSPS for GHG, as long as the EPA 

provides a rational basis for doing so. 

However, in each rule, the EPA 

acknowledged that some stakeholders 

had argued that the EPA first needed to 

make a pollutant-specific SCF, that is, a 

finding that GHG from the source 

category contributes significantly to 

dangerous air pollution. In each rule, 

the EPA stated that it disagreed with 

those stakeholders, but nevertheless, in 

the alternative, did make a pollutantspecific SCF for GHG, supported by the 

same reasons that the EPA had used to 

determine that it had a rational basis to 

regulate GHG. See 80 FR 64529 through 

64531 (2015 EGU Rule); 81 FR 35840 

through 35843 (2016 Oil & Gas Rule). 

In the 2018 Proposal, in which the 

EPA proposed to revise the 2015 Rule, 

the EPA solicited comment on whether 

to adopt the interpretation that it was 

required to make an SCF for GHG from 

the EGU source category before it could 

promulgate an NSPS for CO2. Some 

commenters stated that the EPA must 

make pollutant-specific findings of 

endangerment and significant 

contribution in order to establish an 

NSPS for that pollutant. These 

commenters explained that in their 

view, CAA section 111(b)(1)(A) requires 

the EPA to make two specific findings: 

(1) The specific ‘‘air pollution’’ to be 

regulated is ‘‘reasonably . . . 

anticipated to endanger public health or 

welfare;’’ and (2) the specific source 

category ‘‘causes or contributes 

significantly to’’ that air pollution. 

Commenters asserted that CAA section 

111(b)(1)(A) is not ambiguous in this 

respect, and, therefore, the Agency’s 

interpretation in the 2015 Rule directly 

contradicts the plain language of that 

section. 

Other commenters stated that the 

EPA’s approach in the 2015 Rule, that 

it needs to determine only that it has a 

rational basis to regulate GHGs emitted 

by this source category as a prerequisite 

to regulation, is sound. They said in the 

context of CAA section 111, the SCF 

and endangerment finding are made 

with respect to the source category, and 

not as to specific pollutants. These 

commenters supported the conclusion 

in the 2015 Rule that the EPA possesses 

authority to regulate GHG emissions 

from fossil fuel-fired EGUs under CAA 

section 111 because there was no new 

evidence calling into question its 

determination that GHG air pollution 

may reasonably be anticipated to 

endanger public health and welfare and 

fossil fuel-fired EGUs have a high level 

of GHG emissions. The commenters 

stated that these considerations hew 

closely to the statutory factors that 

inform the decision whether to list a 

source category in the first place— 

namely, whether the category ‘‘causes, 

or contributes significantly to, air 

pollution which may reasonably be 

anticipated to endanger public health or 

welfare,’’ under CAA section 

111(b)(1)(A). The commenters added 

that this approach, which closely 

parallels the listing analysis but does 

not require a formal endangerment 

finding or SCF, is legally sound. They 

also added that the statute is clear that 

a formal endangerment finding is 

required to initially list a sector to be 

regulated under CAA section 111; but it 

is also clear that such a finding is not 

required before regulating additional 

harmful pollutants from a previouslylisted sector.7

Similarly, in a 2019 proposal to revise 

the 2016 Oil & Gas Rule, the EPA 

solicited comment on whether to adopt 

the interpretation that it was required to 

make an SCF for GHG from the Oil and 

Gas source category before it could 

promulgate a CH4 NSPS. Recently, the 

EPA completed the final rule to revise 

the 2016 Oil & Gas Rule, ‘‘Oil and 

Natural Gas Sector: Emission Standards 

for New, Reconstructed, and Modified 

Sources Review: Final Rule,’’ 85 FR 

57018 (September 14, 2020) (2020 Oil & 

Gas Rule). There, the EPA determined 

that a pollutant-specific SCF is required. 

In addition, the EPA further determined 

that the pollutant-specific SCF in the 

2016 Oil & Gas Rule was invalid on 

grounds, in part, that the EPA had not 

established a threshold or criteria by 

which to determine whether an amount 

of emissions contributes significantly to 

dangerous air pollution, and to 

distinguish from an amount of 

emissions that simply contributes to 

dangerous air pollution. The EPA stated 

2546 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

that section 111(b) of the CAA requires, 

or at least authorizes, a pollutantspecific SCF, and such an SCF must be 

based on defined criteria or thresholds. 

Id. at 57033–40. 

B. What is a Significant Contribution 

Finding (SCF)? 

1. Significant Contribution Finding and 

Key Comments Received 

CAA section 111 directs the EPA to 

regulate, through a multi-step process, 

air pollutants from categories of 

stationary sources. CAA section 

111(b)(1)(A) requires the initial action, 

which is that the Administrator must 

‘‘publish . . . a list of categories of 

stationary sources. He shall include a 

category of sources in such list if in his 

judgment it causes, or contributes 

significantly to, air pollution which may 

reasonably be anticipated to endanger 

public health or welfare.’’ Therefore, the 

first action that the EPA must take, 

specified in CAA section 111(b)(1)(A), is 

to list a source category for regulation 

on the basis of a determination that the 

category contributes significantly to 

dangerous air pollution. This provision 

makes clear that although Congress 

designed CAA section 111 to apply 

broadly to source categories of all types 

wherever located, Congress also 

imposed a constraint: The EPA is 

authorized to regulate only sources that 

it finds cause or contribute significantly 

to air pollution that the EPA finds to be 

dangerous. Because CAA section 

111(b)(1)(A) refers to air pollution, the 

EPA’s determination that a source 

category should be listed for regulation 

can be based on all pollutants emitted 

by the category (i.e., collective 

contribution), or for a specific pollutant. 

After the EPA lists a source category, 

CAA section 111(b)(1)(B) then directs 

the EPA to propose regulations 

‘‘establishing Federal standards of 

performance’’ for new sources within 

the source category, to allow public 

comment, and to ‘‘promulgate . . . such 

standards with such modifications as he 

deems appropriate.’’ CAA section 

111(a)(1) defines the term ‘‘standard of 

performance’’ as ‘‘a standard for 

emissions of air pollutants which [the 

Administrator is required to determine 

through a specified methodology].’’ 

These provisions read together make 

clear that the standards of performance 

that CAA section 111(b)(1)(A) directs 

the Administrator to promulgate must 

concern air pollutants emitted from the 

sources in the source category. 

However, industrial sources of the type 

subject to CAA section 111(b)(1)(A) 

invariably emit more than one air 

pollutant, and neither CAA section 

111(b)(1)(B) nor CAA section 111(a)(1), 

by their terms, specifies for which of 

those air pollutants the EPA must 

promulgate standards of performance. 

In the past, the EPA has interpreted 

CAA section 111(b)(1)(B) to authorize it 

to promulgate standards of performance 

for any air pollutant that the EPA 

identified in listing the source category 

and any additional air pollutant for 

which the EPA has identified a rational 

basis for regulation. 81 FR 35843 (2016 

Oil & Gas Rule); 80 FR 64510 (2015 

Rule). Inherent in this approach is the 

recognition that CAA section 

111(b)(1)(A) does not, by its terms, 

necessarily require the EPA to 

promulgate standards of performance 

for all air pollutants emitting from the 

source category. The EPA could list a 

source category on grounds that it emits 

numerous air pollutants that, taken 

together, significantly contribute to air 

pollution that may reasonably be 

anticipated to endanger public health or 

welfare, and proceed to regulate each of 

those pollutants, without ever finding 

that each (or any) of those air pollutants 

by itself causes or contributes 

significantly to—or, in terms of the text 

of other provisions, causes or 

contributes to—air pollution that may 

reasonably be anticipated to endanger 

public health or welfare. 

As described in the 2020 Oil and Gas 

Policy Rule, CAA section 111(b)(1)(A) 

does not provide or suggest any criteria 

to define the rational basis approach, 

the EPA has not articulated any criteria 

in its previous applications in the EGU 

CO2 NSPS and the 2016 40 CFR part 60, 

subpart OOOOa rules, and in instances 

before those rules in which the EPA has 

relied on the ‘‘rational basis’’ approach, 

the EPA has done so to justify not 

setting a standard for a given pollutant, 

rather than to justify setting such a 

standard. 85 FR 77037, December 1, 

2020. Thus, the rational basis test allows 

the EPA virtually unfettered discretion 

in determining which air pollutants to 

regulate. As a result, the rational basis 

standard creates the possibility that the 

EPA could seek to promulgate NSPS for 

pollutants that may be emitted in 

relatively minor amounts. 

In contrast, CAA section 111(b)(1)(A) 

is clear that the EPA may list a source 

category for regulation only if the EPA 

determines that the source category 

‘‘causes or contributes significantly’’ 

(emphasis added) to dangerous air 

pollution. As described in the 2020 Oil 

and Gas Policy Rule, in light of the 

stringency of this statutory requirement 

for listing a source category, it would be 

unreasonable to interpret CAA section 

111(b)(1)(B) to allow the Agency to 

regulate air pollutants from the source 

category merely by making an 

administrative determination under the 

open-ended and undefined rational 

basis test. The EPA, therefore, 

determined it is logical to interpret CAA 

section 111(b)(1)(B) to require that the 

Agency apply the same degree of rigor 

in determining which air pollutants to 

regulate as it does in determining which 

source categories to list for regulation, 

and, therefore, must make a pollutantspecific SCF. Id. 

Requiring a pollutant-specific SCF 

necessitates the establishment of a 

clearer framework for assessing which 

air pollutants merit regulatory attention 

that will require sources to bear control 

costs. The establishment of such a 

framework or criteria promotes 

regulatory certainty for stakeholders and 

consistency in the EPA’s identification 

of which air pollutants to regulate and 

reduces the risk that air pollutants that 

do not merit regulation will 

nevertheless become subject to 

regulation due to an unduly vague 

standard. 

As previously described, CAA section 

111(b)(1)(B) requires the EPA to 

establish an NSPS for a source category 

listed under CAA section 111(b)(1)(A). 

For a source category previously listed 

under CAA section 111(b)(1)(A), in 

order to subsequently promulgate an 

NSPS for a pollutant that the EPA did 

not evaluate the source category for at 

the time of listing, the EPA must make 

a pollutant-specific SCF for the reasons 

described above. As part of making an 

SCF, the EPA concluded in the 2020 Oil 

and Gas Policy Rule that, ‘‘a standard or 

an established set of a criteria, or 

perhaps both, are necessary to identify 

what is significant and what is not.’’ 85 

FR 57039. The EPA did not finalize or 

take a position in the 2020 Oil and Gas 

Policy Rule on potential criteria, stating 

that it was deferring the identification of 

such criteria to a future rulemaking. Id. 

CAA section 111(b) itself does not 

specify what the criteria for a pollutantspecific SCF. 

The ‘‘contributes significantly’’ 

provision in CAA section 111(b)(1)(A) is 

ambiguous as to what level of 

contribution is considered to be 

significant. See 84 FR 50267 and 50268, 

September 24, 2019 (citing EPA v. EME 

Homer City Generation, L.P., 572 U.S. 

489 (2014) (holding that a similar 

provision in CAA section 110(a)(2)(D)(i), 

often termed the ‘‘good neighbor’’ 

provision, is ambiguous)). Accordingly, 

the EPA has authority to interpret that 

provision. Id. at 50268. As noted above, 

the EPA reads CAA section 111(b)(1)(B) 

in light of CAA sections 111(b)(1)(A) 

and 111(a)(1) to incorporate the 

‘‘contributes significantly’’ standard in 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2547 

connection with promulgating NSPS for 

particular air pollutants. The EPA has 

concluded that to allow the EPA to 

distinguish between a contribution and 

a significant contribution to dangerous 

pollution, some type of (reasonably 

explained and intelligible) standard 

and/or established set of criteria that 

can be consistently applied is necessary. 

A supporting basis for this conclusion 

can be found by looking at the EPA’s 

interpretation of the similarly worded 

‘‘contribute significantly’’ provisions of 

CAA section 189(e), concerning major 

stationary sources of particulate matter 

with a diameter of 10 micrometers or 

less (PM10). This provision requires that 

the control requirements applicable to 

major stationary sources of PM10 also 

apply to major stationary sources of 

PM10 precursors ‘‘except where the 

Administrator determines that such 

sources [of precursors] do not contribute 

significantly to PM10 levels which 

exceed the standard in the area.’’ As the 

EPA noted in the 2019 Oil and Gas 

Policy Rule proposal, in CAA section 

189(e), Congress intended that, in order 

to be subject to regulation, the emissions 

must have a greater impact than a 

simple contribution not characterized as 

a significant contribution. However, 

Congress did not quantify how much 

greater. Therefore, the EPA developed 

criteria for identifying whether the 

impact of a particular precursor would 

‘‘contribute significantly’’ to a NAAQS 

exceedance. 84 FR 50268. These criteria 

included numerical thresholds. Id. The 

EPA concluded similarly that, under 

CAA section 111(b), a standard or an 

established set of a criteria, or perhaps 

both, are necessary to identify what is 

significant and what is not. 

These criteria help ensure that the 

EPA’s decision-making is well-reasoned 

and consistent. The EPA considers it 

particularly important to develop a set 

of criteria and/or a standard in order to 

determine when a significant 

contribution occurs, in order, as noted 

above, to distinguish it from a simple 

contribution. A contribution can be 

greater or lesser and remain a 

contribution, but a significant 

contribution determination necessarily 

involves a judgment about the degree of 

the contribution that rises to the level of 

significance. For such a judgment to be 

meaningful (and, of critical importance, 

to be understood by regulated parties 

and by the public), the Agency must 

identify the criteria it will use to 

determine significance. 

2. Other Comments Received on the 

EPA’s Basis for Regulating GHG 

Emissions from EGUs 

Comment: Commenters stated that the 

EPA must make the specific pollutant 

findings of endangerment and 

significant contribution that are 

required in listing a source category in 

order to establish a NSPS for that 

pollutant. Commenters stated they are 

not arguing that the EPA could not or 

should not make these findings. Rather, 

that the Clean Air Act (CAA) requires 

the EPA to make two specific findings: 

(i) The specific ‘‘air pollution’’ to be 

regulated is ‘‘reasonably . . . 

anticipated to endanger public health or 

welfare’’; and (ii) the specific source 

category ‘‘causes or contributes 

significantly to’’ that endangering air 

pollution. CAA section 111(b)(1)(A). 

The commenters said section 

111(b)(1)A) is not ambiguous at all in 

this respect, and therefore the Agency’s 

interpretation in the 2015 Rule directly 

contradicts the plain language of this 

section. Additionally, they said that in 

the 2009 Endangerment Finding, the 

EPA specifically defined air pollution, 

as referred to in section 202(a) of the 

CAA, to be the mix of six long-lived and 

directly emitted GHGs: CO2, CH4, N2O, 

HFCs, PFCs, and SF6 (74 FR 66497, 

December 15, 2009). They commented 

that the EPA did not make a separate 

finding then, or now, that CO2 alone is 

a danger to the public health or welfare 

and the EPA has argued that because 

CO2 is the ‘‘dominant anthropogenic 

GHG,’’ it is not required to ‘‘make an 

endangerment finding with respect to a 

particular pollutant.’’ (Id). They argued 

that this view does not satisfy the 

statutory standard and said the GHG 

endangerment determination in section 

111(b)(1)(A) is fundamentally different 

than that in section 202(a) and other 

CAA sections, in part because it: (i) Is 

source-category based; and (ii) requires 

a finding of significance. 

These commenters stated that in the 

2015 Rule, the EPA made three 

arguments as to why it believed it had 

met its statutory obligations. The 

commenters stated that none of these 

arguments are correct as a legal matter 

for the following primary reasons: (1) 

The EPA was wrong in claiming that 

new CO2-specific findings were 

unnecessary, as the 2015 Rule was for 

a new category of electric utility 

generating unit (EGUs) emitting CO2—a 

specific pollutant for which an 

endangerment finding had not been 

made. EPA’s prior listings of ‘‘steam 

generators’’ and ‘‘stationary gas 

turbines’’ covered only emissions of 

NOX, SO2, and particulate matter. 

Because EPA’s findings in earlier 

listings addressed different pollutants, 

those listings triggered and authorized 

only regulation of NOX, SO2, and 

particulate matter. Cf. Nat’l Asphalt 

Pavement Ass’n v. Train, 539 F.2d 775 

(D.C. Cir. 1976). EPA has asserted the 

authority to regulate under section 111 

any pollutant for which EPA believes it 

has a ‘‘rational basis’’ to regulate (see 83 

FR 65432; 80 FR 64530). But this 

‘‘rational basis’’ standard is not the one 

authorized by section 111; the 

endangerment and significant 

contribution standard governs section 

111 regulation. EPA cannot rewrite the 

statute to circumvent the endangerment 

and significant contribution standard 

that Congress prescribed for section 111 

regulation.; (2) the EPA cannot rely on 

its 2009 finding regarding GHG 

emissions from automobiles which 

determined that ‘‘six well-mixed GHGs’’ 

in the ‘‘aggregate’’ endanger public 

health or welfare, as this ‘‘combined 

mix’’ is different air pollutant than the 

single pollutant controlled here (CO2

alone). EPA has never found that CO2

alone endangers public health or 

welfare, much less that CO2 from fossil 

fuel-fired steam generating units (as 

opposed to motor vehicles) has that 

effect; and (3) the EPA’s attempt to rely 

on ‘‘information and conclusions’’ 

contained in the 2015 Rule does not 

satisfy the CAA. Simply identifying the 

evidence that might support a finding is 

not the same as completing the 

administrative process of distilling and 

analyzing that data in the context of the 

Agency’s statutory obligations and its 

failure to make the requisite findings of 

endangerment and significant 

contribution in the 2015 Rule violated 

the CAA. They said the CAA grants the 

EPA narrowly bounded authority to 

regulate stationary sources that emit 

pollutants that may reasonably be 

anticipated to endanger public health or 

welfare for those pollutants which led to 

the endangerment finding and to which 

the source category significantly 

contributes. The CAA does not grant the 

Agency unlimited authority to regulate 

any pollutant emitted by that source. 

Accordingly, before the EPA finalizes 

the 2018 Proposal, it must make a 

specific and supportable finding that 

CO2 emissions from fossil fuel-fired 

EGUs pose a danger to public health and 

welfare. They said the EPA should reject 

its ill-founded ‘‘rational basis test’’ for 

imposing performance standards 

without endangerment and contribution 

findings. The Agency’s rational basis 

test is not in the CAA. They argued that 

section 111 never uses the term and the 

case law on which the EPA relied for 

2548 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

this test addresses agency authority 

under a different statute, the 

Administrative Procedure Act (APA). 

The APA does not define the scope of 

the EPA’s authority to undertake this 

rulemaking. 

Commenters added that as a textual 

matter, the endangerment requirement 

modifies, and relates back to, ‘‘air 

pollution,’’ not ‘‘sources’’: The 

provision requires the EPA to determine 

whether a source causes or contributes 

significantly to ‘‘air pollution which 

may reasonably be anticipated to 

endanger public health or welfare.’’ 42 

United States Code (U.S.C.) section 

7411(b)(1)(A). Only after the EPA 

determines that a pollutant poses a 

threat to ‘‘public health or welfare’’ 

must it inquire whether the particular 

category of sources ‘‘contributes 

significantly’’ to that pollution. Id. The 

idea that an endangerment finding is 

‘‘one and done’’ on a source level also 

cannot be squared with the surrounding 

statutory requirements. Section 

111(b)(1)(B) provides that the EPA may 

issue performance standards after a 

source category is listed pursuant to 

section 111(b)(1)(A). Id. section 

7411(b)(1)(B). Yet by definition, a 

‘‘standard of performance’’ is tied to 

specific pollutants for which an 

endangerment finding has been made. 

Id. section 7411 (a)(1) (defining a 

‘‘standard of performance’’ as ‘‘a 

standard for emissions of air pollutants). 

Commenters said that as such, the 

approach in the 2015 Rule would give 

the EPA unfettered authority to regulate 

any air pollutant emitted by a source 

regardless of whether it endangers 

health or welfare and the 2015 Rule’s 

approach of mixing and matching 

elements of endangerment findings 

would allow the EPA to impose 

stringent regulations on sources that do 

not ‘‘contribute significantly’’ to 

emissions of a pollutant. In summary, 

the commenters argued that if the EPA 

‘‘retain[s]’’ the ‘‘statutory interpretation’’ 

of section 111 as set out in the 2015 

Rule, 83 FR 65432 n. 25, it will once 

again be setting standards beyond the 

scope of its authority and it may be that 

the EPA can make the findings section 

111(b)(1)(A) requires for CO2 emissions 

from fossil-fuel-fired electricity 

generating units, but unless and until 

the EPA makes those determinations 

under the proper legal standard, the 

Proposed Rule will rest on a flawed 

foundation. 

Commenters stated that the previous 

endangerment findings the EPA listed in 

the 2015 Rule did not relate to ‘‘fossil 

fuel-fired electricity generating units.’’ 

(80 FR 64527 nn.86 & 87). Rather, one 

related to ‘‘steam generators,’’ (36 FR 

5931, March 31, 1971,—cited at 80 FR 

64527 n.86), and the other to ‘‘stationary 

gas turbines,’’ (42 FR 53657. October 3, 

1977,—cited at 80 FR 64527 n.87). The 

commenters stated that this failing 

should prevent the EPA’s ability to 

move forward with proposed regulation 

because the Agency has not issued the 

required endangerment finding for the 

specific source category, it becomes 

irrelevant whether it may rely on that 

(nonexistent) finding to justify setting 

standards of performance for different 

emissions from sources in the category. 

Commenters stated that in the 2016 

subpart OOOOa rulemaking, the EPA 

established NSPS for CH4 without 

making an endangerment finding for 

CH4 emissions from oil and gas sources. 

Commenters and other industry groups 

filed comments pointing out the EPA’s 

omission in failing to make a section 

111(b) endangerment finding for the 

new pollutant subject to regulation 

under NSPS. By imposing NSPS 

requirements for a new pollutant 

without first establishing that that 

pollutant ‘‘may reasonably be 

anticipated to endanger public health or 

welfare’’ (i.e., making an endangerment 

finding), commenters urged the EPA to 

reject and withdraw the interpretation 

that the EPA may skip the 

endangerment finding step in this 

context. The commenters further urged 

the EPA to clarify that a statutory 

prerequisite for regulation of a new 

pollutant under the NSPS program is an 

endangerment finding for that particular 

pollutant. Finally, and as a separate 

matter, the commenters urged the EPA 

to revisit the legal underpinnings for the 

subpart OOOOa standards as the 

commenters asserted the EPA did not 

follow the statutory prerequisites for the 

adoption of such standards. According 

to the commenters, those standards are 

illegal as being outside of the agency’s 

authority, and as such should now be 

withdrawn. 

Other commenters stated that the 

EPA’s previous approach in the 2015 

Rule to determining that it has a rational 

basis to regulate GHGs emitted by this 

source category is sound. The Agency 

has correctly not reopened this 

approach, nor has it proposed any 

alternatives to it. They said in the 

context of section 111, the 

endangerment finding is made with 

respect to the source category, and not 

as to specific pollutants (80 FR 64530). 

It would be unlawful for the Agency to 

finalize any alternative approach. In 

2015, the EPA concluded that it 

possesses authority to regulate GHG 

emissions from fossil fuel-fired EGUs 

under section 111 for two reasons: (1) 

There was no new evidence calling into 

question its determination that ‘‘GHG 

air pollution may reasonably be 

anticipated to endanger public health 

and welfare’’; and (2) fossil fuel-fired 

EGUs have a ‘‘high level of GHG 

emissions.’’ These considerations hew 

closely to the statutory factors that 

inform the decision whether to list a 

source category in the first place— 

namely, whether the category ‘‘causes, 

or contributes significantly to, air 

pollution which may reasonably be 

anticipated to endanger public health or 

welfare.’’ In fact, in 2015 the Agency 

confirmed that, even if it were required 

to issue endangerment and significant 

contribution findings under this 

provision in order to regulate GHGs 

emitted by EGUs, the same information 

that underpinned its rational basis 

conclusion would support such findings 

(80 FR 64530). This approach, which 

closely parallels the listing analysis but 

does not require formal endangerment 

or cause-or-contribute findings, is 

legally sound. The statute is clear that 

a formal endangerment finding is 

required to initially list a sector to be 

regulated under section 111—and is also 

clear that such a finding is not required 

before regulating additional harmful 

pollutants from a previously-listed 

sector. Because Congress did not 

provide specific criteria for regulating 

additional pollutants from a source 

category that is already listed under 

section 111, it is reasonable to look to 

the statutory factors that trigger 

regulation initially when deciding 

whether to require reductions of other 

pollutants. They said the statutory 

factors for listing a source category—the 

endangerment and cause-or-contribute 

findings—provide a floor for when EPA 

must regulate an additional pollutant 

from a listed source category under the 

rational basis inquiry. It would be 

irrational to fail to regulate an 

additional pollutant simply because a 

source category was already listed, if the 

same evidence regarding that pollutant 

would have triggered a formal listing of 

that source category had the source 

category not previously been listed. 

Thus, it would be arbitrary for the 

agency to decline to regulate a pollutant 

on the basis of considerations wholly 

unrelated to the harms that pollutant 

poses or the quantities in which it is 

emitted from a particular source 

category. 

Other commenters also stated that any 

effort to reverse the EPA’s decision to 

regulate CO2 from power plants would 

require, among other things, that the 

EPA fully contend with each step of the 

statutory and legal analysis of section 

111 it undertook in the 2015 Rule, and 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2549 

explain why each of them has become 

invalid. They said promulgating a final 

rule contrary to the 2015 Rule without 

the requisite record-based, factual 

analysis and reasoned explanation 

would yield ‘‘an unexplained 

inconsistency in agency policy’’ that is 

arbitrary, capricious, and unlawful. 

Commenters stated that that while the 

most comprehensive approach to 

sensible GHG regulation remains 

through congressional action, and while 

the CAA is far from the perfect tool for 

regulating GHGs, it is preferable to 

protracted legal battles and to the 

potential patchwork of judicial and 

regulatory outcomes. As a result, the 

Agency should retain the existing 

endangerment finding. They said that if 

the EPA fails to regulate GHG emissions 

from new coal-fired EGUs it would be 

wholly unreasonable and contrary to the 

endangerment finding. 

Response: The EPA addressed the 

substance of these comments in a 

lengthy discussion in ‘‘Oil and Natural 

Gas Sector: Emission Standards for 

New, Reconstructed, and Modified 

Sources Review: Final Rule,’’ 85 FR 

57018, 57033–40, 57052–58 (September 

14, 2020). That discussion is 

incorporated by reference here. That 

discussion further elaborates the 

rationale for EPA’s determination that a 

pollutant-specific significant 

contribution determination is 

appropriate, and EPA’s related 

determinations. That discussion also 

responds in full to the comments on the 

present rule. 

It should be noted that in the 2015 

Rule, EPA combined the steam 

generating source category and 

combustion turbine source category into 

a single source category for purposes of 

GHG emission regulation, 80 FR 64510, 

64521–32 (October 23, 2015), and 

determined, in the alternative, that GHG 

emissions from the combined source 

category contribute significantly to 

dangerous air pollution. Id. at 64531. In 

today’s rulemaking, the EPA is not 

revising the source category 

determination in the 2015 Rule and, by 

the same token, the significant 

contribution finding that EPA is making 

in the present rulemaking for GHG 

emissions concerns emissions from the 

same, combined source category. 

Comment: Commenters stated that if 

the Endangerment Finding is 

overturned, the electric power sector 

could be broadly exposed to tort and 

nuisance suits brought by citizens and 

states—as was the case prior to the EPA 

regulation of GHGs (e.g., American 

Electric Power Co. v. Connecticut, 564 

U.S. 610 (2011)). Accordingly, these 

efforts would create more uncertainty 

about the future of GHG regulations 

applicable to new EGUs—uncertainty 

that likely would not be resolved for 

years and could undermine any 

potential for generation owners and 

operators to consider new coal-based 

generation as a viable option. They said 

as a result, the Agency should retain the 

existing endangerment finding. 

Response: The Agency has not 

proposed to overturn the existing 

Endangerment Finding and is not 

overturning it in this final rule. 

Comment: Commenters stated that to 

the extent that emissions of CO2 from 

new, modified, or reconstructed electric 

utility generating units are to be 

subjected by the EPA to regulation 

under the CAA, the proper path would 

be to regulate such emissions as part of 

a broader effort to regulate CO2

emissions from ‘‘numerous or diverse’’ 

sources under sections 108–110 of the 

CAA. Alternatively, if the EPA is 

adamant in engaging in regulating such 

emissions under section 111(b), at the 

very least the EPA must complete a 

specific endangerment finding for CO2

emissions from such facilities under the 

applicable criteria set forth in section 

111(b), which the EPA has failed to do 

to date. Either way, commenters stated 

that the proposed rule amendment is 

beyond the legal authority of the CAA. 

Response: EPA is making a pollutantspecific significant contribution finding 

in this action. 

Comment: Commenters quoted the 

NSPS proposal as stating that ‘‘the 

Agency will consider comments on the 

correctness of the EPA’s interpretations 

and determinations, and whether there 

are alternative interpretations that may 

be permissible, either as a general 

matter or specifically as applied to GHG 

emissions’’ (83 FR 65242, 65432 n.25). 

Commenters then stated that they filed 

a petition in 2017 contending that the 

EPA should commence a new 

rulemaking on the subject of the 

Agency’s 2009 endangerment finding. 

They provided the following arguments 

of the 2017 petition: (1) There had been 

no statistically significant atmospheric 

warming despite a continued increase in 

atmospheric CO2 levels; (2) changes in 

global temperatures in recent decades 

were far from unusual; (3) new balloon 

and satellite data showed that the 

atmosphere was far less sensitive to CO2

forcing than the climate models had 

predicted; and (4) there was mounting 

evidence that the EPA’s GHG rules 

would have no discernible climate 

impact. For these reasons, they said 

there was a need to reexamine both the 

three lines of evidence for the EPA’s 

endangerment finding as well as its 

underlying rationale. Regarding the 

proposal, the commenters stated that in 

addition to their still pending petition, 

they are providing new evidence for 

why the Agency should proceed with 

this petition and with similar petitions 

pending before it. They submitted 

references (titles, weblinks, and 

synopses) to nine research papers 

published since filing their initial 

petition which they argue add 

additional support. They stated that 

given the points and data outlined in 

this newer research, in addition to those 

set forth in their 2017 petition, the EPA 

should commence a new proceeding to 

reexamine its 2009 endangerment 

finding. 

Response: The Agency is retaining the 

existing endangerment finding. The 

submitted material is out of scope for 

this rulemaking. With regards to the 

claim that EPA was soliciting comments 

on this subject, the footnote quoted by 

the commenters goes on to specifically 

outline examples of the kind of 

comments referred to: This further 

elaboration made clear that EPA was not 

soliciting comments on the science of 

climate change but rather regarding 

interpretation of statutory language and 

legal opinion as to whether the Agency 

would need to make an endangerment 

finding for previously listed source 

categories (‘‘For example, the Agency 

will consider comments on the issue of 

whether it is correct to interpret the 

‘‘endangerment finding’’ as a finding 

that is only made once for each source 

category at the time that the EPA lists 

the source category or whether the EPA 

must make a new endangerment finding 

each time the Agency regulates an 

additional pollutant by an already-listed 

source category. Further, the EPA will 

consider comments on the issue of 

whether GHG emissions are different in 

salient respects from traditional 

emissions such that it would be 

appropriate to conduct a new 

‘‘endangerment finding’’ with respect to 

GHG emissions from a previously listed 

source category. In addition, the EPA 

solicits comment on whether the 

Agency does have a rational basis for 

regulating CO2 emissions from new 

coal-fired electric utility steam 

generating units and whether it would 

have a rational basis for declining to do 

so at this time’’ 83 FR 65242, 65432 

n.25). 

Comment: Commenters also said that 

the Agency suggestion in footnote 25 of 

the Proposal is unreasonable in that the 

Agency seems to presume that it might 

not be appropriate to regulate GHGs 

from new coal-fired power plants 

because the Agency projects that few 

such plants will be built in coming 

years. They said this approach asks the 

2550 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

wrong question. The question should be 

whether there is a rational basis to 

regulate GHGs from power plants—not 

just new coal-fired plants. This is 

because, once new sources are regulated 

under section 111(b), the obligation to 

regulate existing sources under section 

111(d) is triggered. If new sources in a 

source category could not be regulated 

under section 111(b), no sources in the 

category could be regulated. 

Commenters further stated that the EPA 

cannot reverse its position merely by 

asking for comments on whether it 

should adopt a new position 

diametrically opposed to both current 

law and the position it maintains in the 

Proposed Rule. 

Commenters stated that using footnote 

25 as a means of requesting public 

comment is misleading and violates 

administrative procedures. They said 

that it appears that the EPA is seeking 

rationale or justification to under the 

legal basis for this rule while claiming 

that is retaining its legal basis. The EPA 

cannot have it both ways: either EPA is 

using its legal basis, or it is looking for 

alternatives. If it is looking for 

alternatives, then EPA has not met its 

responsibilities under the 

Administrative Procedures Act for fair 

notice of the nature and scope of this 

rulemaking. 

Commenters stated that in the 

endangerment finding footnote of the 

2018 Proposal (83 FR 65432 n 25), the 

EPA suggests that it may consider 

whether it would have a rational basis 

to decline to regulate given that ‘‘no 

more than a few new coal-fired EGUs 

can be expected to be built.’’ The 

commenters said this suggestion is not 

legally or factually sound and does not 

provides a valid reason not to regulate 

GHGs from fossil fuel-fired EGUs under 

section 111. They said the statute is 

unambiguous: The EPA must consider 

pollution from both new and existing 

sources when deciding whether to 

regulate a pollutant within a source 

category. To the extent that the statute 

contains any ambiguity, a decision not 

to regulate based solely on projected 

levels of emissions from new sources 

would be disallowed as an 

impermissible construction. They 

argued that section 111(b) 

unambiguously expresses Congress’s 

concern with pollution emitted from a 

source category as a whole, not just new 

sources and 111(b) directs the 

Administrator to base decisions about 

whether to list a source category on an 

analysis of the entire category, including 

existing sources. Section 111(b)(1)(A) 

does not distinguish between ‘‘new’’ 

and ‘‘existing’’ sources but rather 

conveys Congress’s directive to address 

pollution across the source category. 

The commenters also stated that 

Footnote 25 of the proposal raises the 

prospect that, on the question of 

regulating a pollutant from a listed 

source category, Congress inexplicably 

intended for the EPA to consider 

pollution from new sources only, 

irrespective of the harm caused by 

pollution from existing sources—and 

even though Congress directed the EPA 

to consider the air pollution from the 

sector as a whole, that plain language 

should be ignored. They said the 

Agency presents no support for this 

theory, which is contrary to both the 

clear terms and the evident objective of 

the statute. The commenters argued that 

Footnote 25’s suggested interpretation 

disregards statutory language in other 

ways as well. For example, section 

111(b)(1) provides that the 

Administrator ‘‘shall include a category 

of sources in such list if in his judgment 

it causes, or contributes significantly to, 

air pollution which may reasonably be 

anticipated to endanger public health or 

welfare.’’ (42 U.S.C. 7411(b)(1)(A)). Yet 

as of the date of when the EPA 

determines to list a source category, 

there are no ‘‘new’’ sources in existence. 

Section 111(a)(2) provides: ‘‘The term 

‘‘new source’’ means any stationary 

source, the construction or modification 

of which is commenced after the 

publication of regulations (or, if earlier, 

proposed regulations) prescribing a 

standard of performance under this 

section which will be applicable to such 

source.’’ (Id. section 7411(a)(2)). They 

said under section 111, listing precedes 

promulgation of standards. So, when the 

EPA decides whether to list a category, 

by definition it has not yet proposed 

section 111 standards for that category 

and because it has not proposed such 

standards, no sources qualify as ‘‘new’’ 

sources under section 111(a)(2). Basing 

a decision not to list (and therefore not 

to regulate) a source category solely on 

the absence of emissions from as yet 

nonexistent ‘‘new’’ sources—while 

ignoring sources that already exist and 

are emitting pollutants that threaten 

harm to public health and welfare—is 

not a tenable reading of the statutory 

language. 

Response: In this rule, EPA takes the 

position that GHG emissions from new 

and existing EGUs contribute 

significantly to dangerous air pollution. 

While EPA proposed to retain the 

position that it stated in the 2015 Rule 

that a pollutant-specific significant 

contribution finding is not required, it 

solicited comment on whether such a 

finding is required, and that comment 

solicitation provided adequate notice. 

Comment: Commenters stated that 

though the EPA notes that it is not 

proposing to revisit its 2009 

endangerment finding for greenhouse 

gases, the proposed NSPS revisions 

request comment on whether recent and 

projected power sector trends present a 

rational basis to decline to regulate CO2

emissions from the power sector. The 

suggested comment area, presented in 

footnote 25, cites power sector trend 

projections from the Energy Information 

Administration’s (EIA’s) 2018 Annual 

Energy Outlook and findings from the 

EPA’s proposed Affordable Clean 

Energy (ACE) rule as potential support 

for this position. Commenters also 

stated that the EIA’s 2018 Annual 

Energy Outlook does not indicate that 

power sector CO2 emissions will decline 

significantly in the future. Instead, the 

estimates referenced by the EPA in the 

proposal project that CO2 emissions 

from the power sector will remain the 

single largest sector-based source of CO2

emissions over the long term, totaling 

1.72 billion tons in 2020, 1.71 billion 

tons in 2030, and 1.78 billion tons in 

2050. Commenters said though the EPA 

found that the transportation sector 

overtook the power sector as the largest 

sector-based source of GHG emissions in 

2017, the 2018 Annual Energy Outlook 

projects that power sector emissions 

will regain the top ranking in 2026 and 

maintain a lead over the transportation 

sector by growing modestly through 

2050. Commenters stated while newer 

EIA projections that were unavailable at 

the time of the EPA’s proposal indicate 

slightly lower power sector CO2

emissions, EIA still projects significant 

and sustained power sector GHG 

emissions through 2050, not a steady 

decline. Commenters said a report from 

the Rhodium Group based on 

preliminary EIA data for 2018 and 

released a few weeks after the EPA’s 

proposal estimates that power sectorrelated GHG emissions increased 3.4 

percent in 2018, breaking a three-year 

trend of decreases. Commenters added 

still more recent EPA data reveals the 

same pattern. Commenters stated 

preliminary 2018 emissions data 

compiled by EPA’s Clean Air Markets 

Division (CAMD), also released after the 

proposed NSPS revisions were 

published in the Federal Register, show 

power sector CO2 emissions rising from 

1.92 billion tons in 2017 to 1.93 billion 

tons in 2018. Commenters said prior to 

the 2018 release, EPA’s CAMD data had 

shown flat or declining CO2 emissions 

for every year since 2013. 

Commenters stated it would be 

unlawful and arbitrary for the EPA to 

use declining power sector emissions as 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2551 

reason for not regulating. They argued 

that even if power sector emissions are 

declining—which is not at all clear— 

they are far higher than levels necessary 

to keep CO2 concentrations from rising 

further, let alone to achieve the 

necessary net-zero balance. CO2

pollution accumulates in the 

atmosphere, where it lingers for 

centuries, such that a year-to-year 

decline in emissions does not prevent 

atmospheric concentrations from 

continuing to rise, exacerbating the 

impacts of climate change. ‘‘[T]he 

urgency of reducing emissions now,’’ 

(80 FR 64520) which the EPA 

acknowledged in the 2015 Rule, has 

only increased in recent years. 

Commenters said reliance on recent 

emission trends is even more 

unfounded because U.S. climate 

pollution significantly increased in 

2018, including a 1.9 percent increase in 

power sector carbon pollution. Even 

before the 2018 data were available, U.S. 

Energy Information Administration 

(EIA) had recognized long-term market 

and economic uncertainty, which could 

potentially drive some shift back to coal 

generation. EIA projections now show 

that the general trend toward declining 

carbon pollution from the power sector 

is likely to flatten out in the early 2020s. 

Commenters stated standards that even 

if pollution levels were declining more 

steadily, that would not authorize the 

EPA to ignore its obligation to protect 

the public from what will continue to be 

a major threat to public health and the 

environment. The CAA is not concerned 

merely with whether pollution levels 

are currently below their historic peak. 

To the contrary, the Agency must ensure 

that pollution is controlled to the degree 

the statute requires—i.e., in accordance 

with a standard of performance that 

reflects the best system of emission 

reduction (BSER) (42 U.S.C. 7411(a)(1)). 

The commenters also said that there 

may be other reasons why a developer 

would be willing to pay a premium to 

build a new coal-fired plant that the 

models do not consider (80 FR 64559– 

64562). Thus, it is unreasonable not to 

establish standards of performance on 

the assumption that coal-fired power 

plants will never again be built (or 

modified). They said that the Agency 

does not even consider the fact that the 

source category includes not only new 

sources but also existing sources that 

undergo certain ‘‘modifications,’’ and 

that such modified sources have 

significant CO2 emissions. 

Commenters said that by asking 

whether the Agency has a rational basis 

for regulating CO2 emissions from new 

coal-fired EGUs ‘‘in light of’’ the 

projections cited in footnote 25, the EPA 

is setting itself up to conduct continual 

market evaluations for all the EPA 

regulations for which regulation is 

premised on a similar type of 

prerequisite determination. An 

interpretation of section 111 that leads 

to that result is unreasonable and 

impractical. They said that there is no 

indication in the CAA that Congress 

intended the Agency to undertake a 

continual market assessment of this 

nature. 

Commenters stated that the 

endangerment finding footnote of the 

2018 Proposal (83 FR 65432 footnote 25) 

contains a fatal factual deficiency in that 

it suggests that the rational basis finding 

might be reversed because ‘‘no more 

than a few new coal-fired EGUs can be 

expected to be built, which raises 

questions about whether new coal-fired 

EGUs contribute significantly to 

atmospheric CO2 levels.’’ The 

commenters said that not only does this 

suggestion disregard the EPA’s 2015 

acknowledgment that ‘‘the CO2

emissions from even a single new coalfired power plant may amount to 

millions of tons each year,’’ but it 

entirely ignores natural gas-fired power 

plants, which are also included in the 

source category. In making the 2015 

determination, the EPA specifically 

observed that ‘‘the CO2 emissions from 

even a single natural gas combined 

cycle (NGCC) unit may amount to one 

million or more tons per year.’’ They 

said natural gas-fired power plants 

continue to be built at a steady clip as 

evidenced by the first ten months of 

2018 in which 14.9 gigawatts (GW) of 

natural gas-fired EGU capacity was 

added to the grid. New gas plants must 

be accounted for and by failing to do so, 

the Agency would forfeit any ‘‘rational 

connection between the facts found and 

the choice made,’’ and would fail to 

provide ‘‘a reasoned explanation . . . 

for disregarding facts and circumstances 

that underlay . . . the prior policy.’’ 

Each of those flaws would render the 

decision arbitrary and capricious. 

Commenters said that even if the EPA 

legally could regulate CO2 emissions 

from new natural gas plants without 

regulating CO2 emissions from new 

coal-fired power plants, the EPA should 

not do so because such partial 

regulation would provide an inadvertent 

subsidy to new coal-fired plants. 

Response: In this rule, the EPA is 

determining that GHG emissions from 

EGUs contribute significantly to 

dangerous air pollution and is 

promulgating revised standards of 

performance for EGU GHG emissions. 

To the extent it is useful or necessary in 

this rulemaking for the EPA to further 

address whether long-term emission 

trends, or related considerations, are 

relevant for a significant contribution 

determination, the EPA does so 

elsewhere in this document. 

C. Primary Criteria for Determining 

Significance 

In this section, the EPA describes 

criteria for determining when GHG 

emissions from a source category 

contribute significantly to dangerous air 

pollution in response to comments 

submitted on this rule. The EPA 

indicated in the 2020 Oil and Gas Policy 

Rule that it would finalize these criteria 

in a separate rulemaking. 85 FR 57039. 

1. GHG Emissions 

The criteria discussed herein only 

apply to GHG in the context of the 

EPA’s SCF under CAA section 

111(b)(1)(B). This action does not 

discuss criteria for pollutants other than 

GHGs. Under this framework, the EPA 

is determining that the quantity of GHG 

emissions from a source category is the 

primary criterion in determining 

significance for purposes of regulation 

of GHGs from a source category under 

CAA section 111(b). Gross GHG 

emissions are important for this set of 

pollutants because GHGs are global 

long-lived pollutants and do not have 

the local, near-term ramifications found 

with other pollutants (e.g., criteria 

pollutants). Unlike other pollutants 

where both the location and quantity of 

pollution emissions are factors in 

determining the impact of the 

emissions, GHGs’ impact (i.e., climate 

change) is based on a cumulative global 

loading and the location of emissions is 

not nearly as important a factor as it is 

for assessing local, near-term impacts 

associated with criteria pollutants. It is 

for this reason that, when the EPA is 

assessing GHGs impact in contributing 

significantly to air pollution which may 

reasonably be anticipated to endanger 

public health and welfare, the quantity 

of emissions should be the primary 

criterion that the EPA should evaluate. 

The GHG emissions are the best, but 

not necessarily only, indicator of 

significance because the quantity of 

emissions emitted from a source 

category correlates directly with 

impacts. Calculations using the Model 

for the Assessment of Greenhouse Gas 

Induced Climate Change (MAGICC 

model) to investigate the impact of 

including or eliminating a single 

sector’s emissions from 2020 through 

2100 have shown that the magnitude of 

emissions from that single sector is very 

close to being linearly related to the 

projected temperature change in 2100 

resulting from eliminating that sector’s 

emissions. This is consistent with the 

2552 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

8H. Damon Matthews, Nathan P. Gillett, Peter A. 

Stott & Kirsten Zickfeld, The Proportionality of 

Global Warming to Cumulative Carbon Emissions. 

Nature 459, 829–832 (2009), available at https://

www.nature.com/articles/nature08047. 

9By the same token, as the EPA explained in the 

2020 Oil & Gas Rule, there are limits to the EPA’s 

ability to expand a source category to include other 

sources. As the EPA stated in that rule, ‘‘the 

authority to revise the scope of a source category 

must be exercised within reasonable boundaries 

and cannot be employed in a way that results in an 

unreasonable expansion of an existing source 

category. . . . [T]he EPA is not authorized to 

expand the scope of a listed source category to 

cover a new set of sources that are not sufficiently 

related to the sources in the pre-existing 

category. . . ’’ 85 FR 57027. 

results of a number of peer reviewed 

publications in the past decade: e.g., 

Matthews et al. found that the 

temperature change is roughly 

proportional to the total quantity of CO2

emissions over a wide range of potential 

scenarios.8

A threshold of GHG emissions from 

the source category compared to the rest 

of the U.S. GHG emissions (i.e., the 

percent of total U.S. GHG emissions) 

can be used to demonstrate significance. 

Emissions can be large enough from a 

source category that the evaluation of 

GHG emissions in isolation is sufficient 

for making a finding of significance for 

the source category. Conversely, the 

EPA believes that some source 

categories are sufficiently small in GHG 

emissions that a finding of 

insignificance can be made by only 

evaluating the GHG emissions from the 

source category. For many source 

categories, the evaluation of GHG 

emissions alone will be sufficient for 

determining whether there is significant 

contribution. 

It should be noted that under section 

111(b)(1)(A), the EPA is required to 

make a significance finding on a 

category-by-category basis. That 

provision requires the Administrator to 

list ‘‘a category of sources’’ for 

regulation if he determines that ‘‘it 

causes or contributes significantly to’’ 

dangerous air pollution. Section 

111(b)(1)(A) (emphasis. added). As a 

result, the text of 111(b)(1)(A) compels 

or is at least best read to require the EPA 

to make the significance determination 

for a particular source category on the 

basis of the emissions (or other relevant 

attributes) of that particular source 

category. In contrast, the EPA may not 

combine source categories that 

individually would not meet the 

significance criteria and determine that, 

when combined, the source categories 

do meet the significance criteria.9

2. Using a Threshold in Significance 

Determination 

Under this framework, the EPA is 

determining a threshold for the 

evaluation of significance of GHG 

emissions from source categories. The 

use of a clear threshold provides 

certainty regarding the EPA’s process 

and allows the regulated entities to have 

insight into how the EPA will make 

determinations on significance for their 

respective source category. The 

threshold introduced in this rulemaking 

is a reflection of the EPA’s best 

understanding of the landscape of the 

U.S. GHG emissions from stationary 

sources. The EPA is introducing a 

methodology to evaluate significance 

with respect to the U.S. GHG emissions 

that can be applied for any source 

category, and that application of the 

methodology is only being directly 

applied to the EGU source category in 

this action as further introduction of 

this approach. It is important to note 

that a significance determination for the 

U.S. GHG emissions will be needed 

before the EPA may regulate any other 

source category under CAA section 

111(b) for GHG emissions. 

As Table 1, below, makes clear, there 

are at least two natural breakpoints 

between groups of emitting source 

categories. The first natural breakpoint 

is between EGUs and all other source 

categories. EGUs stand out as by far the 

largest stationary source of the U.S. 

GHG emissions, emitting over 25 

percent of all the U.S. GHG emissions. 

Based on available data, the next largest 

source category, Oil and Natural Gas, 

emits just under 3 percent of U.S. GHG 

emissions. Two other source categories, 

Boilers and Petroleum Refineries, also 

fall between 2.5 percent and 3.0 percent 

of U.S. emissions. Between 1.5 percent 

and 2.5 percent of U.S. GHG emissions 

there is another natural breakpoint and 

all of the remaining source categories 

fall below 1.5 percent of the U.S. GHG 

emissions. Note that source category 

emissions in Table 1 are an estimate of 

what the Agency currently understands 

about the emissions from CAA section 

111 source categories. If the EPA were 

to do a rulemaking and a significance 

determination for a specific source 

category, the EPA would do a thorough 

analysis of the available and attributable 

GHG emissions data to ensure 

appropriate determinations and 

assessments. 

TABLE 1—EXAMINATION OF GHG EMISSIONS FROM LARGE STATIONARY SOURCES OF GHG EMISSIONS

% of total U.S. GHG 

emissions 

Emissions in that range 

(MMT CO2e) * Source categories affected at different thresholds 

Percent of U.S. 

GHG emissions 

from stationary 

sources covered 

at given threshold 

(%) 

Above 25% ............. >1670 MMT ................................ EGUs (1778 MMT/27% of total US GHG Emissions, 3.6% of 

Global emissions).

43 

3% to 25% .............. 200 MMT–1670 MMT ................. No categories identified ................................................................... 43 

2.5% to 3.0% .......... 167–200 MMT ............................ Oil/Gas Production and Processing; ∧ Refineries; Boilers .............. 56 

2.0% to 2.5% .......... 134–167 MMT ............................ No categories identified ................................................................... 56 

1.5% to 2.0% .......... 100–134 MMT ............................ No categories identified ................................................................... 56 

1.0% to 1.5% .......... 67–100 MMT .............................. Landfills;I Iron and Steel ................................................................ 60 

* MMT CO2e = Million metric tons of carbon dioxide equivalent ∧ Note that the oil and gas production and processing GHG emissions are very close to the 3% value and thus there is a possibility that this 

source category may be above the threshold in the near term. 

I Note that the Landfills source category has already been regulated under CAA section 111 and the level of the emissions in Table 1. reflects 

reductions in GHG emissions as a result of that regulation as a co-benefit. 

The EPA is introducing a threshold of 

3 percent of U.S. GHG emissions to 

evaluate a source category’s emissions 

to determine significance for purposes 

of CAA section 111(b). The EPA is also 

determining that source categories that 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2553 

10The EPA recognizes that in the 2016 Oil & Gas 

Rule, it determined that GHG emissions from the oil 

and natural gas source category contribute 

significantly to dangerous air pollution, in part, on 

the grounds that those emissions exceeded the total 

amount of emissions from various foreign countries. 

81 FR 35824, 35840 (June 3, 2016). The EPA 

believes that its current approach of identifying a 

threshold for significance based on a percentage of 

U.S. emissions is better reasoned than the 2016 Oil 

& Gas Rule’s approach of drawing comparisons to 

the absolute emissions of other countries. 

11The EPA does not currently have a 

comprehensive inventory of the U.S. GHG 

emissions for all of the NSPS source categories. For 

the EPA to make determinations of significance for 

a source category, a more comprehensive emissions 

profile of a source category should be used. The 

EPA will make determinations of significance for 

other source categories in the future. 12See 79 FR 34960 and 80 FR 64510. 13Note that one of those ‘‘next three largest’’ 

source categories is oil and natural gas. In the 

recently finalized policy package, the EPA found 

that regulation of GHGs from this source category 

is unnecessary as it is currently being controlled by 

regulation of volatile organic compounds. See 85 FR 

57018, 57030 (September 14, 2020). 

are less than this value (i.e., 3 percent 

or less) are necessarily insignificant 

without consideration of any other 

factors. The reasoning for choosing this 

threshold is presented later in this 

document. 

The EPA acknowledges that, when 

interpreting other CAA provisions, the 

EPA has used different thresholds to 

define ‘‘significant contribution,’’ but it 

is appropriate to select a threshold 

based on the nature of the problem 

being addressed. For example, to 

address the problem of interstate 

transport under CAA section 

111(a)(2)(D)(i)(I)—which concerns 

criteria pollutants, i.e., pollutants that 

affect the NAAQS—the EPA selected a 

threshold of 1 percent based on analysis 

of air quality modeling specific to the 

criteria pollutant at issue. 76 FR 48208, 

48236 (August 8, 2011) (Cross-State Air 

Pollution Rule (CSAPR)). For criteria 

pollutants, both the location and 

quantity of emissions are factors in 

determining their impact. In contrast, 

the impact of GHGs (e.g., climate 

change) is based on a cumulative global 

loading, and the location of emissions is 

not nearly as important a factor as it is 

for assessing local impacts associated 

with criteria pollutants. Because GHGs 

do not have the local near-term impacts 

that criteria pollutants tend to have, a 

larger value is appropriate to use in 

determining significance as it still 

addresses the health and welfare 

impacts of GHG emissions without 

specifically evaluating local near-term 

impacts, which is analytically 

unreasonable to do given the global 

nature of GHGs. While the 3 percent 

threshold will be applied against 

domestic emissions, source categories 

exceeding that threshold represent a 

much smaller fraction of global GHG 

emissions.10

By determining a threshold, the EPA 

is setting a clear indication of how 

source categories will be evaluated for 

significance based on GHG emissions. 

For those source categories that are 

below the 3 percent threshold, the EPA 

would make a determination (through 

future rulemaking) of insignificance. 

This means that if a source category 

collectively emits 3 percent or less of 

the total U.S. GHG emissions, it will be 

considered to be insignificant. For those 

source categories that are above the 

threshold, a more detailed evaluation of 

other criteria can be used to make a 

determination of significance. This is 

described in section IV.D below. It is 

important for the EPA to make this clear 

indication as it allows source categories 

and the general public a level of 

transparency as to how the EPA will be 

evaluating source categories for 

significance. The threshold in this 

action will provide a degree of certainty 

regarding whether a source category will 

later be found significant or 

insignificant based on the threshold.11

After evaluating the two natural break 

points in GHG emissions, the EPA 

determined that 3 percent of the U.S. 

GHG emissions was the best threshold 

for determining significance. As noted 

above, there is currently only one source 

category above this threshold, EGUs, 

and the evaluation of significance for 

the EGU source category has been a 

topic explored and discussed by the 

Agency in great detail over the course of 

the last decade.12 Just below the 3 

percent threshold are three source 

categories: Oil and Natural Gas, 

Petroleum Refineries, and IndustrialCommercial-Institutional Steam 

Generating Units (i.e., ‘‘Boilers’’). There 

are no other source categories with GHG 

emissions between 1.5 percent and the 

3 percent. By using a threshold of 3 

percent of the U.S. GHG emissions (i.e., 

only including EGUs above the 

threshold), the EPA will effectively be 

covering 43 percent of the U.S. 

stationary source GHG emissions via 

regulation of a single source category. If 

the EPA were to instead set a threshold 

between the other identified 

breakpoint—between 1.5 percent and 

2.5 percent of U.S. GHG emissions—the 

EPA observes that this threshold would 

lead to a relatively modest increase in 

the stationary source U.S. GHG 

emissions that would be regulated of an 

additional 13 percent (for a total of 56 

percent of U.S. stationary source GHG 

emissions).13 In addition, regulation of 

the additional source categories that 

comprise 13 percent of U.S. emissions 

would eliminate only a portion of those 

emissions. With an even lower 

threshold of significance set at 1.0 

percent of U.S. GHG emissions, there 

would be significantly more source 

categories covered (about 10 based on 

the EPA estimates) above the threshold 

but likely would include an even more 

modest increase in stationary source 

GHGs that would cover 60 percent of 

U.S. stationary source GHGs. Under this 

framework, the EPA is basing a decision 

to apply a threshold of 3 percent on the 

relative contribution of regulating 

source categories that contribute 

significantly to the overall impact of 

climate change. To that end, the 

temperature impact associated with the 

hypothetical elimination of all source 

categories above a 3 percent threshold 

corresponds to a hypothetical global 

mean temperature reduction of 0.049 

degrees Celsius (°C) (approximately 0.1 

degree Fahrenheit, the calculated effect 

in 2100 of removing 1,780 million 

metric tons (MMT) of CO2 emissions 

each year from 2020 through 2100) from 

source categories above that threshold 

(i.e., just EGUs). Eliminating the next 

largest source category (i.e., Oil and Gas 

Processing and Production) would only 

generate an additional hypothetical 

global mean temperature reduction of 

less than 0.01°C and even smaller 

source categories correspondingly 

contribute less to global temperature. 

The EPA is making the decision that the 

threshold for a significance 

determination for U.S. GHG emissions 

to be in the form of a percentage. A 

percentage is a metric that measures the 

relative contribution to the whole and, 

in this action, the EPA believes that it 

is appropriate to measure and evaluate 

significant contribution of U.S. GHG 

emissions as a relative contribution to 

the whole of GHG emissions in the U.S. 

The EPA is determining that a threshold 

in the form of a percentage is both 

reasonable and more appropriate for 

making the significance determination 

in this rule based on a percent’s relative 

nature. This is important because the 

trajectory of U.S. GHG emissions is 

trending down. As overall emissions 

decrease over the course of time, a 

source category’s relative contribution 

to GHGs may not have changed or may 

have even increased based on GHG 

reductions in other source categories 

and sectors. A relative percentage 

threshold recognizes that the EPA may 

later determine a source category is 

significant based on these 

circumstances, because a source 

category’s emissions may eventually 

exceed the threshold even though it is 

currently below the threshold. 

2554 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

14Although there is no source category other than 

EGUs above the 3% threshold, because the 

threshold is a percentage and as previously 

described, other source categories may move into 

this tier as overall GHG emissions decrease and 

other source category emissions increase. 

Accordingly, a percentage threshold 

allows the EPA, over time, to always 

focus on the source categories with the 

potential to have the greatest impact. 

The framework on which EPA bases its 

decision today is, therefore, amenable to 

future use, which augurs in favor of the 

framework’s use to make today’s 

finding. 

The EPA is introducing in this action 

that a threshold in the form of a 

percentage is both reasonable and more 

appropriate for making a significance 

determination for GHGs based on a 

percent’s relative nature. A tonnage 

threshold is a static metric that would 

not change over time. As previously 

described, the trajectory of U.S. GHG 

emissions is trending down. As 

emissions decrease over the course of 

time, it is likely that source categories 

that were once above any static 

threshold will fall below such a 

threshold. Even though a source 

category may reduce overall U.S. GHG 

emissions, that source category’s 

relative contribution to GHGs may not 

have changed or may have even 

increased based on GHG reductions in 

other source categories and sectors. 

Additionally, if emissions do decrease 

over time, the use of a tonnage threshold 

potentially results in no source category 

meeting the criteria for significance, 

even if collectively the U.S.GHG 

emissions continue to pose a danger to 

public health or welfare. 

It should be noted that the U.S. GHG 

emissions of the EGU source category 

are more than an order of magnitude 

larger than the emissions threshold in 

the framework, representing 43 percent 

of U.S. stationary source GHG 

emissions. The EPA believes that it is 

possible for source categories with GHG 

emissions substantially larger than the 

threshold to be deemed significant on 

the basis of the primary criterion alone 

(i.e., magnitude of emissions) and 

without consideration of the secondary 

criteria described elsewhere in this 

notice. 

3. Tiers of Source Categories Based on 

GHG Emissions 

As noted previously, the primary 

criterion in evaluating the significance 

of a source category is, again, the 

relative magnitude of the U.S. GHG 

emissions. The EPA believes that NSPS 

source categories may be grouped into 

three tiers on the basis of magnitude of 

the U.S. GHG emissions, as follows: 

(1) Source category with GHG emissions 

substantially above the threshold. This 

source category has emissions of a large 

enough magnitude that a determination of 

significance can be made on the basis of the 

magnitude of emissions alone. As discussed 

later in this document, this tier is comprised 

solely of the EGUs source category; in other 

words, EGUs do not require consideration of 

the secondary criteria in order to determine 

significance. 

(2) Source categories with an intermediate 

magnitude of the U.S. GHG emissions (i.e., 

those with emissions above the threshold but 

less than the quantity emitted by the EGU 

source category). For source categories with 

emissions above the threshold, evaluation of 

the magnitude of the U.S. GHG emissions is 

inconclusive. Rather, a significance 

determination requires an examination of the 

source category’s magnitude of emissions 

combined with a more detailed look at the 

secondary criteria discussed elsewhere in 

this document. 

(3) Source categories with a small 

magnitude of GHG emissions (i.e., those with 

emissions below the threshold). Source 

categories with a small magnitude of 

emissions will be deemed insignificant based 

on evaluation of the primary criterion alone, 

without detailed consideration of any 

secondary criteria. 

D. Secondary Criteria for Determining 

Significance 

As described above, the EPA is 

determining that the U.S. GHG 

emissions from a source category are the 

primary and most important criterion 

for making a determination of 

significance for a source category. 

However, there may be instances where 

the U.S. GHG emissions from a source 

category do not give a comprehensive 

enough picture to make a determination 

of significance. The threshold that the 

EPA has described above in Section 

IV.B would provide a clear indication 

that the U.S. GHG emissions from 

source categories below that threshold 

are necessarily insignificant. However, 

under this framework, for any source 

category that is above that threshold, 

there are other source-category specific 

considerations that should be evaluated 

in addition to GHG emissions when 

making a determination of 

significance.14 For that reason, the EPA 

will consider other, secondary, criteria 

in the evaluation of significance for 

certain source categories. These other 

criteria are described in the subsequent 

subsections. It is important for the EPA 

to consider secondary criteria in the 

evaluation of significance for certain 

source categories because the criteria 

provide unique context to the source 

category beyond the information 

provided by the magnitude of the source 

category’s GHG emissions. 

1. Evaluation and Context of GHG 

Emissions 

Under the introduced framework, the 

evaluation of the magnitude of the U.S. 

GHG emissions from a source category 

is a substantial indicator of whether a 

source category is significant, but in the 

specific instance of source categories 

that have greater GHG emissions than 

the threshold, an evaluation based on 

the magnitude of the U.S. GHG 

emissions may be inconclusive. Within 

the introduced framework, there are 

other emissions-based metrics that must 

be evaluated to clarify and make a 

significance determination for these 

source categories. 

a. Source Category Trends 

An important criterion that can help 

illuminate and contextualize a 

significance determination is an 

evaluation of the trends in emissions 

and number of designated facilities 

within a source category. Primarily, the 

EPA is evaluating whether a source 

category is on a trajectory of the U.S. 

GHG emission decline. If the source 

category, as a whole, is decreasing its 

GHG emissions, an explanation for why 

it is on the decline may aid in making 

a significance determination. In one 

scenario, if the source category is 

decreasing emissions because the source 

category is declining in production or 

other output (e.g., due to decreasing 

demand for goods or other market 

conditions, due to relocation overseas, 

or due to the cumulative effect of 

regulations), it may lend towards an 

insignificance determination as the 

emissions are already declining and 

expected to continue to decline even 

without further regulation. In a separate 

scenario, if a source category’s GHG 

emissions are declining due to increased 

efficiency and updated technology, it 

may lend towards a determination of 

significance. This would allow the EPA 

the ability to regulate the source 

category in order to ensure that 

efficiency and technology 

improvements become standard across 

the source category through both an 

NSPS (111(b) regulation) for new, 

modified and reconstructed sources and 

an emission guidelines (111(d) 

regulation) for existing sources. 

In a scenario in which the EPA were 

to find a source category to be growing 

in either emissions or number of 

designated facilities (or both), it could 

lend towards that source category being 

found to be significant. This would 

allow EPA to regulate and mitigate 

emissions from new, modified and/or 

reconstructed designated facilities 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2555 

15 If U.S. production shifted overseas to a 

jurisdiction that has laxer environmental 

regulations, for a global pollutant such as mercury 

or GHGs, there could be both increased local 

environmental and health impacts at the new 

overseas location and domestic impacts to the U.S. 

resulting from the increased U.S. GHG emissions. 

16For this purpose, EGUs include the affected 

sources in the combined source category for boilers 

and turbines. In the 2015 Rule, the EPA 

‘‘combine[d] the two categories of EGUs—steam 

generators and combustion turbines—into a single 

category of fossil fuel-fired EGUs for purposes of 

promulgating standards of performance for CO2

emissions.’’ 80 FR 64529 (2015 Rule). 

within that source category under CAA 

section 111(b) (i.e., via a NSPS). 

If the EPA were to evaluate the trend 

in the number of designated facilities 

and emissions of a source category, it 

might show a static number of existing 

facilities with a constant or slightly 

increasing quantity of the U.S. GHG 

emissions. In this scenario, there may be 

little utility in determining significance 

for that source category and 

consequentially developing a NSPS as 

there are little to no emissions that 

would be subject to such a standard. 

However, creating a NSPS for a source 

category and pollutant is a necessary 

predicate to regulating existing sources 

under CAA section 111(d). Hence, in the 

scenario of a static number of existing 

facilities, a finding of significance for 

the source category may be warranted as 

it would allow eventual regulation of a 

group of existing source categories. 

Under this framework, the EPA expects 

the prospect of regulating a source 

category under CAA section 111(d) for 

existing sources to be a compelling 

reason for determining significance. 

b. Source Category Emissions With 

Global Context 

Another important criterion that the 

EPA considers, as a secondary factor, is 

the relative contribution of GHG 

emissions from the U.S. in a specific 

source category compared to worldwide 

emissions of similar sources. As 

previously described, Section 

111(b)(1)(A) of the CAA states that the 

Administrator shall include source 

categories that contribute significantly 

to endangerment of health and welfare. 

When evaluating a global pollutant such 

as GHGs, the EPA views the impact of 

domestic emissions from domestic 

sources as a more germane 

consideration when determining 

whether a pollutant contributes 

significantly to endangerment of health 

or welfare. Because every ton of GHG 

contributes to the global problem, a 

domestic ton will still have some impact 

in the U.S. Accordingly, it is reasonable 

for the EPA to evaluate whether a source 

category is well-regulated 

internationally and whether the U.S. 

emissions from that sector make up a 

relatively large share of GHG emissions 

on a worldwide scale, as such 

evaluation in turn would inform 

whether U.S. emissions are significantly 

contributing to domestic impacts. If the 

emissions from the U.S. are 

comparatively a large contribution to 

source category/sector emissions 

worldwide, it may lend towards a 

finding of significance for the source 

category based on the U.S.’s substantial 

global contribution to the source 

category. If, however they are relatively 

small, it would suggest less benefit from 

the EPA regulation of that source 

category. 

The EPA also considers, as one of the 

secondary criteria, an evaluation of 

whether a source category is vulnerable 

to being trade exposed (i.e. whether the 

source category is constrained in the 

sources’ ability to pass through carbon 

costs due to actual or potential 

international competition). The EPA 

evaluates whether regulation of the 

source category would create a financial 

incentive for that source category/ 

industry to move into, or increase 

production in, another country. This 

could be manifested as either a shift in 

production to facilities internationally 

or a complete closure of existing 

designated facilities in the U.S. It is not 

the EPA’s intention in regulating source 

categories to drive production from the 

U.S. to other countries, and there is an 

environmental concern in pushing 

industries to other international 

locations. This concern is based on the 

potential for these new international 

emissions to increase compared to the 

corresponding displaced U.S. 

emissions.15 While this is always a 

concern for the EPA in the regulation of 

industry within the U.S., it even more 

pronounced with the consideration of 

GHG emissions. As discussed, 

previously, the U.S. GHG emissions are 

a global pollutant that also have 

domestic impacts. As such, if a smaller 

quantity of domestic GHG emissions 

would be displaced, due to a regulation, 

by a greater quantity of international 

GHG emissions it may support a finding 

of insignificance for a given source 

category. This would occur if the U.S. 

sources are already significantly lower 

emitting in GHG emissions than sources 

in other countries. It should also be 

noted that source categories whose 

sources in the U.S. make up a relatively 

smaller proportion of the world’s 

emissions from corresponding 

international sectors may be particularly 

vulnerable to being trade exposed as 

there is likely a greater international 

capacity to absorb the displaced U.S. 

production. 

Given the global nature of GHG 

emissions, assessing and understanding 

the estimated potential net emissions 

impact of GHG control technologies 

provides useful context in which to 

consider the significance of a given set 

of GHG emissions In addition, there 

may also be value in evaluating and 

considering the technology with the 

associated source category (i.e., intrinsic 

to the process of the source category)— 

a prime example of reductions 

associated with this evaluation might be 

assessing the likely impacts of efficiency 

improvements. From a public welfare 

and human health perspective, targeting 

source categories that provide the 

largest overall possible scope for 

emissions reductions could be an 

intrinsic part of determining the 

significance of a given magnitude of 

emissions. Thus, the EPA is determining 

that it is appropriate in a given instance 

to consider feasible technologies 

(including efficiency improvements) for 

further context in the Agency’s 

determination of significance of a source 

category’s overall emissions. Here, the 

magnitude of GHG emissions from EGUs 

coupled with the reductions available 

through efficiency improvements 

supports the EPA’s determination of 

significance. 

d. Temporal Evaluation of Criteria 

As introduced in this framework, the 

evaluation of the secondary criteria is 

not intended to be performed in 

isolation. Rather, the EPA considers the 

weight of evidence of all the factors 

(both primary and secondary) to make 

an informed and comprehensive 

decision as to whether a source category 

that exceeds the 3-percent threshold 

contributes significantly to the U.S. 

GHG emissions. The consideration of 

criteria also has a temporal 

consideration to a significance 

determination. A source category’s 

determination can be reevaluated in the 

future as the status and criteria 

described here may have changed for 

that source category. For example, the 

technology to adequately regulate GHGs 

from a source category may not be 

readily available at this time, but in the 

future that technology may become 

more broadly available causing the EPA 

to then make a SCF. 

E. Significant Contribution Finding for 

EGUs 

As noted above, the Agency is 

finalizing a determination that GHG 

emissions from EGUs 16 contribute 

significantly to dangerous air pollution. 

The primary criterion in determining 

2556 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

17See Table 3–9, Inventory of U.S. Greenhouse 

Gas Emissions and Sinks: 1990–2018, Report 430– 

R–20–002, April 13, 2020, https://www.epa.gov/ 

ghgemissions/inventory-us-greenhouse-gasemissions-and-sinks-1990-2018. 

18The global warming potential (GWP) of a 

greenhouse gas is defined as the ratio of the 

accumulated radiative forcing within a specific time 

horizon relative to that of the reference gas CO2. 

Total GHG emissions are the GWP-weighted 

emissions of all GHG emissions and reported in 

million metric tons of CO2 equivalent (MMT CO2e.). 

19See Table 3–9, Inventory of U.S. Greenhouse 

Gas Emissions and Sinks: 1990–2018, Report 430– 

R–20–002, April 13, 2020, https://www.epa.gov/ 

ghgemissions/inventory-us-greenhouse-gasemissions-and-sinks-1990-2018. 

20 In 2016, worldwide GHG emissions were 

estimated to have been 49.4 gigaton (Gt) CO2e. The 

GHG emissions of China, India, Russia, and 

Indonesia are 11,577, 3,235, 2,391, and 2,229 MMT 

CO2e respectively. https://www.wri.org/blog/2020/ 

02/greenhouse-gas-emissions-by-country-sector. 

21According to Table 8 of the Annual Energy 

Outlook (AEO) 2020, while coal fired generation 

will decline between 2019 and 2025 from 959 

billion kWh to 709 billion kWh, generation from 

coal-fired EGUs is projected to subsequently remain 

relatively steady through 2050. 

22According to Table 8 of the AEO 2020, natural 

gas fired generation is projected to increase from 

1,322 billion kWh to 1,629 billion kWh. 

whether to make a SCF is the magnitude 

of GHG emissions from a given source 

category. It is readily apparent that 

EGUs emit a uniquely large amount of 

GHGs compared to all other categories 

of stationary sources. The EPA made 

this clear in the 2015 Rule, quoted 

above, and reiterated it in the 2020 Oil 

& Gas Rule: ‘‘the unique CO2 emissions 

profile of fossil fuel-fired EGUs should 

be noted: the volume of emissions from 

EGUs dwarfs the amount of GHG 

emissions from every other source 

category.’’ 85 FR 57039, n.49. 

Although GHG emissions from EGUs 

have fallen since the EPA promulgated 

the 2015 Rule, they still remain 

uniquely large among stationary source 

categories. The EPA’s Inventory of U.S. 

Greenhouse Gas Emissions 17 indicates 

that, as of 2018, the Electric Power 

sector directly emitted 1,778.5 MMT of 

GHGs.18 This amount was more than 

twice the amount of GHGs emitted by 

all other industrial sources combined 

and more than all other industrial, 

commercial, and residential stationary 

combustion sources combined.19 In 

addition, direct GHG emissions from 

EGUs account for approximately 27 

percent of total U.S. GHG emissions and 

43 percent of U.S. stationary source 

emissions. The direct GHG emissions 

from EGUs account for approximately 4 

percent of total worldwide GHG 

emissions and are greater than the 

emissions of all but four countries.20

These facts confirm that at current 

emission levels, EGUs have measurable 

impacts on both the U.S. contribution to 

GHG emissions and the worldwide total 

GHG emissions and continue to be 

uniquely large stationary source 

emitters of GHGs. It should be noted 

that if domestic EGUs no longer emitted 

any GHG emissions, there would be a 

measurable impact on worldwide GHG 

emissions and between 2020 and 2100, 

there would be a reduction in the 

projected increase in global 

temperatures by 0.049 degrees Celsius 

(° C). 

Because EGUs represent by far the 

largest stationary source of GHGs from 

combustion of fossil fuels, the EPA 

believes that this is the most appropriate 

place for the EPA, states, and sources to 

devote resources to reducing GHGs from 

stationary sources. Indeed, this uniquely 

large magnitude of emissions is the 

reason over the last 8 years, the Agency 

has devoted significant effort to 

determine how to best reduce GHGs 

from EGUs. Because EGUs are a 

relatively large U.S. source of emissions 

in an overall large pool of international 

EGU sources, regulation over time could 

help produce practices and technologies 

that have application to EGUs 

worldwide. 

It is noteworthy that GHG emissions 

from EGUs are approximately an order 

of magnitude greater than the estimated 

emissions of the second largest 

stationary source category of GHGs 

attributed to combustion, industrial 

boilers. Because the magnitude of GHG 

emissions from EGUs is large compared 

to other stationary sources, this makes 

them clearly significant even without 

detailed consideration of other factors. 

As mentioned earlier, the EPA is also 

introducing a framework under which a 

source category that emits above a 

threshold of 3 percent of U.S. stationary 

source GHG emissions may contribute 

significantly to dangerous GHG air 

pollution. For those source categories 

above that threshold, the EPA is also 

determining that consideration of 

certain secondary criteria may, 

collectively, also inform the evaluation 

of whether a source category should be 

considered to significantly contribute. 

However, within this framework, that 

analysis of secondary criteria is not 

necessary in the case of EGUs, due to 

the overwhelmingly large emissions of 

the source category; it is clear that 

controlling GHG emissions from the 

EGU source category will be necessary 

to appropriately address dangerous air 

pollution. This conclusion is consistent 

with the EPA’s 2018 Proposal where the 

Agency explained that if the EPA was 

required to evaluate significance, EGUs 

would be considered significant. 

1. Secondary Criteria 

The EPA is determining that the 

uniquely large GHG emissions from 

EGUs makes a finding of significant 

contribution and regulation appropriate 

by itself. Under the introduced 

framework, while the EPA does not 

think it is necessary to consider 

secondary criteria because of the 

uniquely large emissions from the EGU 

source category, as explained below, the 

EPA would make the same 

determination even if it did consider 

those criteria. 

a. Source Category Trends 

As mentioned earlier, an important 

criterion is the evaluation of the trends 

in emissions and number of designated 

facilities within a source category, such 

that the EPA can evaluate whether a 

source category is on a trajectory of U.S. 

GHG emission decline. 

While electricity demand is projected 

to increase the U.S., due to the 

increased use of less carbon intensive 

generation technologies and more 

efficient generation, GHG emissions 

from the power sector are projected to 

remain relatively steady for the 

foreseeable future. However, EGUs are 

projected to remain the single largest 

stationary source of GHG emissions, and 

while the Agency expects few, if any, 

new coal-fired EGUs will be built to 

meet the demand for electricity, coalfired EGUs are expected to continue to 

supply electricity and emit significant 

GHG emissions for the foreseeable 

future.21 The EGU source category also 

includes stationary combustion 

turbines. The EPA expects new simple 

cycle and combined cycle combustion 

turbine EGUs will be built in the future 

and that the existing fleet of combustion 

turbines will continue to operate.22

Therefore, efficient generation 

technology could eventually become 

standard for all new and existing EGUs. 

Consequently, the EPA would consider 

the source category trends as supporting 

the regulation of GHG emissions from 

EGUs. 

b. Source Category Emissions With 

Global Context 

The EPA is also determining that it 

can consider, as a secondary criterion, 

the relative contribution of GHG 

emissions from the U.S. in the specific 

source category compared to worldwide 

emissions of similar sources. 

Accordingly, the EPA evaluates whether 

a source category is well-regulated 

internationally and whether the U.S. 

emissions from that sector make up a 

relatively large share of global GHG 

emissions, as such evaluation in turn 

would inform whether U.S. emissions 

are significantly contributing to 

Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 2557 

23U.S. EGU emissions from the Inventory of U.S. 

Greenhouse Gas Emissions and Sinks: 1990–2018, 

Report 430–R–20–002, April 13, 2020, https://

www.epa.gov/ghgemissions/inventory-usgreenhouse-gas-emissions-and-sinks-1990-2018. 

Worldwide EGU emissions from the International 

Energy Agency estimates IEA (2020), CO2 Emissions 

from Fuel Combustion, https://www.iea.org/ 

subscribe-to-data-services/co2-emissions-statistics. 

24Fossil fuel-fired utility steam generating units 

(i.e., boilers) are most often operated using coal as 

the primary fuel. However, some utility boilers use 

natural gas and/or fuel oil as the primary fuel. 

domestic impacts. In this instance, this 

criteria points towards a finding of 

significance given that U.S. EGUs make 

up a sizeable portion (13 percent of the 

emissions) from EGUs worldwide.23

As mentioned earlier in this notice, 

the EPA is also introducing that one of 

the secondary criteria is an evaluation of 

whether a source category is vulnerable 

to being trade exposed (i.e., whether the 

source category is constrained in its 

ability to absorb regulatory costs due to 

actual or potential international 

competition). Concerns about 

international competition would not 

impact the Agency’s decision to regulate 

EGUs because electricity must be 

transported over power lines and it is 

not as easy to relocate or shift 

production locations as it is for other 

source categories. The ability to locate 

generation in Mexico and Canada and 

transmit the power to the U.S. is limited 

because of constraints on existing 

transmission lines and the expense to 

build additional transmission capacity. 

The only additional transmission 

capacity currently being considered is 

for electricity generated from 

hydroelectric power in Canada to 

supply power to New England. Since 

this electricity has a low carbon 

intensity, it would not contribute to an 

overall increase in GHG emissions. 

Furthermore, the emission standards in 

this rule will not increase the costs of 

electricity from a new coal-fired EGU 

such that it might be financially 

advantageous to locate new production 

internationally to countries with less 

stringent regulations. If international 

competition were a concern, the Agency 

would compare the forecast GHG 

emissions from international sources (in 

this case, EGUs in Canada and Mexico) 

against the forecast GHG emissions from 

domestic sources (in this case domestic 

EGUs) in both the absence of and 

implementation of the NSPS. In 

addition, since few, if any, new coalfired EGUs are forecast to be built in the 

U.S., the standards in this final rule will 

not impact electricity prices to end 

users to an extent that other industries 

would be incentivized to relocate 

internationally due to increased 

electricity costs. Therefore, domestic 

reductions in GHG emissions from 

regulating EGUs will not be offset by 

increased international GHG emissions. 

In contrast, for source categories that 

supply raw materials to other domestic 

source categories, the impact of 

international competition on those 

source categories and the resultant GHG 

impacts could be considered when 

determining an appropriate NSPS. It is 

conceivable that an overly stringent 

NSPS could result in an increase in 

global GHG emissions, if the increase in 

international emissions is greater than 

the reduction in domestic emissions. 

V. Summary of Cost, Environmental, 

and Economic Impacts 

A. What are the affected facilities? 

This rule takes final action affecting 

fossil fuel-fired EGUs. These EGUs take 

two forms that are relevant for present 

purposes: Steam generating units (utility 

boilers and gasification units) and 

stationary combustion turbines. Fossil 

fuel-fired steam generating units can 

burn natural gas, oil, or coal. However, 

coal is the dominant fuel for electric 

utility steam generating units. Coal-fired 

steam generating units are primarily 

either PC or fluidized bed (FB) steam 

generating units.24 At a PC steam 

generating unit, the coal is crushed 

(pulverized) into a powder to increase 

its surface area. The coal powder is then 

blown into a steam generating unit and 

burned. In a fossil fuel-fired steam 

generating unit using FB combustion, 

the solid fuel is burned in a layer of 

heated particles suspended in flowing 

air. Power can also be generated from 

coal or other fuels using gasification 

technology. An Integrated Gasification 

Combined Cycle (IGCC) unit gasifies 

coal or petroleum coke to form a 

synthetic gas (or syngas) composed of 

carbon monoxide (CO) and hydrogen 

(H2), which can be combusted in a 

combined cycle system to generate 

power. Stationary combustion turbines 

include both fossil fuel-fired simple 

cycle and combined cycle combustion 

turbine EGUs. 

B. What are the air quality impacts? 

The EPA does not anticipate that this 

final rule for fossil-fuel-fired EGUs will 

result in significant CO2 emission 

changes. 

C. What are the energy impacts? 

This final rule for fossil-fuel-fired 

EGUs is not anticipated to have an effect 

on the supply, distribution, or use of 

energy. 

D. What are the cost impacts? 

The EPA does not believe that this 

final rule for fossil-fuel-fired EGUs will 

have compliance costs associated with 

it. 

E. What are the economic impacts? 

The EPA does not anticipate that this 

final rule for fossil-fuel-fired EGUs will 

result in economic or employment 

impacts. Likewise, the EPA believes this 

rule will not have any impacts on the 

price of electricity, employment or labor 

markets, or the U.S. economy. 

F. What are the benefits? 

The EPA does not anticipate emission 

changes resulting from the final rule for 

fossil-fuel-fired EGUs. 

VI. Statutory and Executive Order 

Reviews 

Additional information about these 

statutes and Executive Orders can be 

found at https://www.epa.gov/lawsregulations/laws-and-executive-orders. 

A. Executive Order 12866: Regulatory 

Planning and Review and Executive 

Order 13563: Improving Regulation and 

Regulatory Review 

This action is a significant regulatory 

action that was submitted to the Office 

of Management and Budget (OMB) for 

review because it raises novel legal or 

policy issues. Any changes made in 

response to OMB recommendations 

have been documented in the docket. 

B. Executive Order 13771: Reducing 

Regulations and Controlling Regulatory 

Costs 

This action is not expected to be an 

Executive Order 13771 regulatory 

action. There are no quantified cost 

estimates for this final rule because the 

EPA does not anticipate this action to 

result in costs or cost savings. 

C. Paperwork Reduction Act (PRA) 

This action does not impose any new 

information collection burden under the 

PRA. OMB has previously approved the 

information collection activities 

contained in the existing parts 75 and 

98 regulations and has assigned OMB 

control numbers 2060–0626 and 2060– 

0629, respectively. 

D. Regulatory Flexibility Act (RFA) 

I certify that this action will not have 

a significant economic impact on a 

substantial number of small entities 

under the RFA. In making this 

determination, the impact of concern is 

any significant adverse economic 

impact on small entities. An agency may 

certify that a rule will not have a 

significant economic impact on a 

2558 Federal Register / Vol. 86, No. 8 / Wednesday, January 13, 2021 / Rules and Regulations 

substantial number of small entities if 

the rule relieves regulatory burden, has 

no net burden, or otherwise has a 

positive economic effect on the small 

entities subject to the rule. The EPA 

expects there to be few, if any, new, 

modified, or reconstructed coal-fired 

EGUs. As such, this final rule would not 

impose significant requirements on 

those sources, including any that are 

owned by small entities. The EPA has, 

therefore, concluded that this action 

will have no net regulatory burden for 

all directly regulated small entities. 

E. Unfunded Mandates Reform Act 

(UMRA) 

This action does not contain an 

unfunded mandate of $100 million or 

more as described in UMRA, 2 U.S.C. 

1531–1538, and does not significantly or 

uniquely affect small governments. This 

action imposes no enforceable duty on 

any state, local, or tribal governments or 

the private sector. 

F. Executive Order 13132: Federalism 

This action does not have federalism 

implications. It will not have substantial 

direct effects on the states, on the 

relationship between the national 

government and the states, or on the 

distribution of power and 

responsibilities among the various 

levels of government. 

G. Executive Order 13175: Consultation 

and Coordination With Indian Tribal 

Governments 

This action does not have tribal 

implications, as specified in Executive 

Order 13175. It would neither impose 

substantial direct compliance costs on 

tribal governments, nor preempt Tribal 

law. The EPA is aware of three coalfired EGUs located in Indian Country 

but is not aware of any EGUs owned or 

operated by tribal entities. The EPA 

notes that this action would affect only 

existing sources such as the three coalfired EGUs located in Indian Country if 

those EGUs were to take actions 

constituting modifications or 

reconstructions as defined under the 

EPA’s NSPS regulations. However, as 

previously stated, the EPA expects there 

to be few, if any, new, reconstructed, or 

modified EGUs. Thus, Executive Order 

13175 does not apply to this action. 

Consistent with the EPA Policy on 

Consultation and Coordination with 

Indian Tribes, the EPA offered 

consultation with tribal officials during 

the development of this action; 

however, the Agency did not receive a 

request for consultation. The EPA held 

meetings with tribal environmental staff 

during the public comment period to 

inform them of the content of the 

proposed rule and to encourage them to 

submit comments on the proposed rule. 

H. Executive Order 13045: Protection of 

Children From Environmental Health 

Risks and Safety Risks 

The EPA interprets Executive Order 

13045 as applying only to those 

regulatory actions that concern health or 

safety risks that the EPA has reason to 

believe may disproportionately affect 

children, per the definition of ‘‘covered 

regulatory action’’ in section 2–202 of 

the Executive Order. This action is not 

subject to Executive Order 13045 

because it does not concern an 

environmental health or safety risk. 

I. Executive Order 13211: Actions 

Concerning Regulations That 

Significantly Affect Energy Supply, 

Distribution, or Use 

This action is not a ‘‘significant 

energy action’’ because it is not likely to 

have a significant adverse effect on the 

supply, distribution, or use of energy 

and has not otherwise been designated 

as a significant energy action by the 

Administrator of the Office of 

Information and Regulatory Affairs 

(OIRA). This final action is not 

anticipated to have impacts on 

emissions, costs, or energy supply 

decisions for the affected electric utility 

industry. 

J. National Technology Transfer and 

Advancement Act (NTTAA) 

This rulemaking does not involve 

technical standards. 

K. Executive Order 12898: Federal 

Actions To Address Environmental 

Justice in Minority Populations and 

Low-Income Populations 

The EPA believes that this action does 

not have disproportionately high and 

adverse human health or environmental 

effects on minority populations, lowincome populations, and/or indigenous 

peoples, as specific in Executive Order 

12898 (59 FR 7629, February 16, 1994), 

because it does not affect the level of 

protection provided to human health or 

the environment. As previously stated, 

the EPA expects that few, if any, coalfired EGUs would be affected by this 

action. 

L. Congressional Review Act (CRA) 

This action is subject to the CRA, and 

the EPA will submit a rule report to 

each House of the Congress and to the 

Comptroller General of the United 

States. This action is not a ‘‘major rule’’ 

as defined by 5 U.S.C. 804(2). 

Andrew Wheeler, 

Administrator. 

[FR Doc. 2021–00389 Filed 1–12–21; 8:45 am] 

BILLING CODE 6560–50–P 

DEPARTMENT OF HOMELAND 

SECURITY 

Federal Emergency Management 

Agency 

44 CFR Part 64 

[Docket ID FEMA–2021–0003; Internal 

Agency Docket No. FEMA–8661] 

Suspension of Community Eligibility 

AGENCY: Federal Emergency 

Management Agency, DHS. 

ACTION: Final rule. 

SUMMARY: This rule identifies 

communities where the sale of flood 

insurance has been authorized under 

the National Flood Insurance Program 

(NFIP) that are scheduled for 

suspension on the effective dates listed 

within this rule because of 

noncompliance with the floodplain 

management requirements of the 

program. If the Federal Emergency 

Management Agency (FEMA) receives 

documentation that the community has 

adopted the required floodplain 

management measures prior to the 

effective suspension date given in this 

rule, the suspension will not occur. 

Information identifying the current 

participation status of a community can 

be obtained from FEMA’s CSB available 

at www.fema.gov/flood-insurance/workwith-nfip/community-status-book. 

Please note that per Revisions to 

Publication Requirements for 

Community Eligibility Status 

Information Under the National Flood 

Insurance Program, notices such as this 

one for scheduled suspension will no 

longer be published in the Federal 

Register as of June 2021 but will be 

available at www.fema.gov. Individuals 

without internet access will be able to 

contact their local floodplain 

management official and/or State NFIP 

Coordinating Office directly for 

assistance. 

DATES: The effective date of each 

community’s scheduled suspension is 

the third date (‘‘Susp.’’) listed in the 

third column of the following tables. 

FOR FURTHER INFORMATION CONTACT: If 

you want to determine whether a 

particular community was suspended 

on the suspension date or for further