Comments, letters, and transcripts of the public hearings are also available electronically through 

http://www.regulations.gov by searching Docket ID EPA-HQ-OAR-2013-0602

EPA’s Responses to Public Comments on the EPA’s

Carbon Pollution Emission Guidelines for Existing Stationary 

Sources: Electric Utility Generating Units

August 2015
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FOREWORD

This document provides the EPA’s responses to public comments on the EPA’s Proposed 

Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric Utility 

Generating Units. The EPA published a Notice of Proposed Rulemaking in the Federal Register

on June 18, 2014, at 79 Fed. Reg. 34830. The EPA received comments on this proposed rule via 

mail, e-mail, facsimile, and at four public hearings held in Atlanta, Georgia; Denver, Colorado; 

Pittsburgh, Pennsylvania; and Washington, D.C., in July and August 2014. The EPA published a 

Supplemental Proposal in the Federal Register on November 4, 2014, at 79 Fed. Reg. 65482. 

The EPA received comments on the supplemental notice to this proposed rule via mail, e-mail, 

facsimile, and a public hearing held in Phoenix, Arizona in November, 2014. Copies of all 

comments and transcripts for the public hearings for both actions are available at the EPA

Docket Center Public Reading Room. Comments and transcripts of the public hearings for both 

actions are also available electronically through http://www.regulations.gov by searching Docket 

ID EPA-HQ-OAR-2013-0602.

The EPA signed and announced the proposed rule on June 2, 2014, and the full text of the 

proposal was available for public review that same day on the EPA website 

(www.epa.gov/cleanpowerplan). The proposed rule was published in the Federal Register on 

June 18, 2014, 79 Fed. Reg. 34830, at which time the 120-day public comment period began, 

ending October 16, 2014. In response to stakeholder requests for additional time to review the 

proposal, the EPA extended the comment period by 45 days, to December 1, 2014. This 

comment period extension gave stakeholders additional time to review all elements of the 

proposal—including the topics highlighted in the Notice of Data Availability (NODA), the 

notice “Additional Information Regarding the Translation of Emission Rate-Based CO2 Goals to 

Mass-Based Equivalents" (79 Fed. Reg. 67406; November 13, 2014), and the technical support 

document (TSD) that provided two examples of how a state, area of Indian country, or territory 

could translate its rate-based goal to total metric tons of carbon dioxide (a mass-based 

equivalent)—and to submit their ideas and suggestions about the proposal, the notices, and the 

TSD. At the close of the comment period on December 1, 2014, the proposal had been available 

for public review for nearly six months (165 days).

Over 4 million public comments were received on the proposal and supplemental notice. The 

EPA Docket Center consolidated approximately 340 mass mail campaigns and petitions into

single document control numbers (DCNs), resulting in approximately 33,700 unique comments. 

Each of these comments was reviewed and all significant comments have been summarized and 

included in this document.

Separately, the EPA published Standards of Performance for Greenhouse Gas Emissions for 

New Stationary Sources: Electric Utility Generating Units (EPA-HQ-OAR-2013-0495) and 

Standards of Performance for Greenhouse Gas Emissions from Modified Sources: Electric 

Utility Generating Units (EPA-HQ-OAR-2013-0603).

This document contains responses to comments on the Emission Guidelines only; responses to 

comments on the NSPS action are in a separate Response to Comments document. This 
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document contains a summary of all significant comments provided by each commenter 

extracted from the original letter or public hearing transcript.

Due to the unprecedented number of comments, lists of document control numbers (DCNs) were 

not included with each comment summary. For purposes of this document, the text within the 

comment summaries was provided by the commenter(s) and represents their opinion(s), 

regardless of whether the summary specifically indicates that the statement is from a 

commenter(s) (e.g., “The commenter states” or “The commenters assert”). The comment 

summaries do not represent the EPA’s opinion unless the response to the comment specifically

agrees with all or a portion of the comment. In some cases the same comment was submitted by 

two or more commenters through submittal of a form letter prepared by an organization, by the 

commenter incorporating by reference the comments in another comment letter, or by the 

commenter providing identical or similar language independently. Rather than repeat these 

comments for each commenter, the EPA has listed the comment only once.

Several of the EPA’s responses to comments are provided immediately following each comment

summary. However, in instances where several commenters raised similar or related issues, the 

EPA has grouped these comments together and provided a single response after the last comment 

summary in the group. In some cases, the EPA provided responses to specific comments or 

groups of similar comments in the preamble to the final rulemaking. Rather than repeating those 

responses in this document, the EPA has referenced the preamble or the appropriate technical 

support document for a description of the analysis included in the final rule.

Many commenters requested that the remarks of other commenters be incorporated into their 

own comments on the proposed rule. Appendix A lists the commenters who have been 

referenced, followed by the number of commenters who asked to incorporate the referenced 

commenters’ remarks.

Many commenters submitted comments to this rulemaking docket that were specific to the NSPS 

action. Some commenters submitted a single DCN with comments on both rules, while others 

submitted a separate DCN specific to each action. Many commenters submitted identical 

comments to both dockets. In order to reduce duplicative comments, we have removed from this 

document comments associated with the NSPS action. For this reason, the EPA encourages the 

public to read the Response to Comment document prepared for the NSPS action.

The Response to Comments Document, together with the preamble to the final Clean Power 

Plan, presents the responses of the Environmental Protection Agency (EPA) to the more than 

four million public comments received on the proposed rule. The EPA has addressed all 

significant issues raised in the public comments.

As a result of changes made to the preamble and final rule prior to signature, and due to the 

volume of comments received, some responses in the Response to Comments Document may not 

reflect the language in the preamble and final rule in every respect. Where the response is in 

conflict with the preamble, the final rule or the legal memorandum, the language in the final 

preamble, rule and the legal memorandum controls and should be used for purposes of 

understanding the scope, requirements, and basis of the final rule. In addition, due to the large 
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number of comments that addressed similar issues, as well as the volume of the comments 

received, the Response to Comments Document does not always cross-reference each response 

to the commenter(s) who raised the particular issue involved. The responses presented in this 

document are intended to augment the responses to comments that appear in the preamble to the 

final rule or to address comments not discussed in that preamble. Although portions of the 

preamble to the final rule are paraphrased in this document where useful to add clarity to 

responses, the preamble itself, along with the legal memorandum, remains the definitive 

statement of the rationale for the revisions adopted in the final rule. In many instances, particular 

responses presented in the Response to Comments Document include cross references to 

responses on related issues that are located either in the preamble to the Clean Power Plan, the 

Technical Support Documents, or elsewhere in the Response to Comments Document. The 

unprecedented number of comments received required on the proposal may have resulted in 

errors or inconsistencies within the Response to Comment Document for the final Clean Power 

Plan. Within the Response to Comments document, where inconsistencies exist, responses to 

legal comments in Chapter 1 take precedence over other responses. All issues on which the EPA 

is taking final action in the Clean Power Plan are addressed in the Clean Power Plan rulemaking 

record.

Accordingly, the Response to Comments Document, together with the preamble to the Clean 

Power Plan and the information contained in the Technical Support Documents, and the rest of 

the administrative record should be considered collectively as the agencies’ response to all of the 

significant comments submitted on the proposed rule. The Response to Comments Document 

incorporates directly or by reference the significant public comments addressed in the preamble 

to the Clean Power Plan as well as other significant public comments that were submitted on the 

proposed rule.
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TABLE OF CONTENTS

CHAPTER 1: LEGAL

1.1 Authority to regulate carbon dioxide

1.2 Authority to regulate EGUs

1.3 Authority to regulate states' energy markets

1.4 Combined categories and codification in the CFR

1.5 Affected sources and applicability

1.6 Implications for Tribes and U.S. Territories

1.7 Endangerment finding

1.8 Building blocks 2, 3, and 4: Intra-state and inter-state compliance

1.9 Potential combinations of the building blocks as components of the BSER

1.10 Determination of the BSER

1.11 State Plan Enforceability Considerations

1.12 Promulgation of rules not proposed

1.13 CAA 307(d)

1.14 Request for extension of comment period

1.15 Other

CHAPTER 2: APPLICABILITY

2.1 Overlap of Sections 111(b) and 111(d)

2.2 Proposed Applicability vs. Broad Applicability

2.3 Applicability issues related to EGUs that fire biomass or other non-fossil fuels

2.4 Applicability issues related to combined heat and power (CHP)

2.5 Definition of Affected Source

2.6 Comments regarding subcategorization

2.7 Other

CHAPTER 3: GHG MITIGATION MEASURES

3.1 Heat Rate Improvement at Existing Coal-fired EGUs (Building Block 1)

3.2 CO2 Reduction Potential from Generation Shifts Among Affected EGUs

(Building Block 2)

3.3 Cleaner Generation Sources (Building Block 3)

3.4 Demand-side Energy Efficiency (EE)

3.5 Alternative RE Approach

3.6 Interaction of Building Blocks

3.7 Fuel Switching

3.8 Carbon Capture & Storage
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3.9 New NGCC capacity

3.10 Heat Rate reduction opportunities for non-coal fossil fuel-fired EGUs

3.11 Potential emission reduction measures not used to set proposed goals

3.12 Other

CHAPTER 4: STATE GOAL COMPUTATION

4.1 Form of Goals

4.2 Proposed Goals

4.3 Alternate Goals

4.4 Computation Procedure

4.5 Errors in 2012 Baseline Data

4.6 Rate-to-mass Conversion

4.7 State flexibilities

4.8 Other goal-setting approaches

4.9 Choice of Baseline Other than 2012

4.10 Tribe and Territory Goals from SNPR

4.11 State-specific goal computation comments

4.12 Other

CHAPTER 5: STATE PLAN CONSIDERATIONS

5.1 State Plan Approaches

5.2 Incorporating end-use energy efficiency and renewable energy programs and

measures under a rate-based approach

5.3 Quantification, monitoring, and verification of end-use energy efficiency

programs and measures

5.4 Quantification, monitoring, and verification for renewable energy programs and measures

5.5 Reporting and recordkeeping for end-use energy efficiency programs and measures

5.6 Reporting and recordkeeping for renewable energy programs and measures

5.7 Treatment of interstate effects

5.8 Projecting EGU CO2 Emission Performance

5.9 Treatment of existing state regulations and programs

5.10 Treatment of New Fossil Fuel-fired EGUs

5.11 Consideration of a facility's "remaining useful life" in applying standards of performance

5.12 Design, Equipment, Work Practice, or Operational Standards

5.13 Emissions averaging and trading

5.14 State-specific Implementation Considerations

5.15 Other

CHAPTER 6: STATE PLANS

6.1 Timing
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6.2 Criteria for Approving State Plans

6.3 State Plan Components

6.4 Process for State Plan Submittal and Review

6.5 Additional Factors

6.6 Resources

6.7 Other

CHAPTER 7: INTERACTIONS WITH OTHER EPA PROGRAMS AND RULES

7.1 EGU NSPS - New

7.2 EGU NSPS - Modified and Reconstructed

7.3 New Source Review (NSR)

7.4 Title V Program

7.5 40 CFR Part 75

7.6 Greenhouse Gas Reporting Program

7.7 Other EPA Rules

7.8 Other

CHAPTER 8: ECONOMIC AND EMPLOYMENT IMPACTS

8.0 Impacts and Costs

8.1 Baseline emissions

8.2 Emission Reductions

8.3 Endangered Species Act

8.4 Energy Impacts 

8.5 Compliance Costs

8.6 Economic and Employment Impacts

8.7 Climate Benefits

8.8 Health and Air Quality Co-Benefits

8.9 Reliable affordable electricity

8.10 Other

CHAPTER 9: STATUTORY AND EXECUTIVE ORDERS

9.1 Executive Order 12866: Regulatory Planning and Review, and

Executive Order 13563: Improving Regulation and Regulatory Review

9.2 Paperwork Reduction Act

9.3 Regulatory Flexibility Act

9.4 Unfunded Mandates Reform Act

9.5 Executive Order 13132: Federalism

9.6 Executive Order 13175, Consultation and Coordination with Indian Tribal Governments

9.7 Executive Order 13045, Protection of Children from Environmental Health Risks

and Safety Risks
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9.8 Executive Order 13211, Actions Concerning Regulations That Significantly

Affect Energy Supply, Distribution, or Use

9.9 National Technology Transfer and Advancement Act

9.10 Executive Order 12898, Federal Actions to Address Environmental Justice

in Minority Populations and Low-Income Populations

CHAPTER 10: RULE LANGUAGE CORRECTIONS

10.1 Definitions (existing)

10.2 Definitions (new)

10.3 Rule language

10.4 Other

CHAPTER 11: GENERAL SUPPORT AND GENERAL OPPOSITION

11.1 General Support

11.2 General Opposition

CHAPTER 12: OTHER

APPENDIX A: CROSS-REFERENCED COMMENTS