### Proposed **Finding under**  **Section 231 of the Clean Air Act**  **that Greenhouse**  **Gas Emissions from Aircraft Cause or Contribute**  **to Air Pollution Which May** **R easonably**  **Be Anticipated**  **to Endanger Public Health and Welfare, and**  **Advance Notice of Proposed Rulemaking** 

# Briefing for OMB March 12, 2015 INTERNAL, DELIBERA TIVE

# Overview

• Rationale for Action under CAA § 231 • Proposed Endangerment Finding under CAA § 231 • Proposed Contribution Finding under CAA § 231 • Advance Notice of Proposed Rulemaking (ANPR) 

## • Schedule

2 INTERNAL, DELIBERA TIVE

# Rationale **for Regulatory A** **ction**

• Aircraft represent 11% of U.S. transportation GHGs

– Largest remaining GHG-emitting transportation source not yet subject to any GHG regulations • The International Civil Aviation Organization (ICAO), at urging of U.S., began efforts to develop aircraft CO 2 standard in 2010 (cited in President’s Climate Action Plan ). Expected to finalize the standard in February 2016. • The Endangerment and Contribution Findings under § 231(a) of the CAA are a necessary first step to potentially adopt equivalent aircraft engine CO 2 standards domestically, wh ich is needed to meet our treaty obligations • ANPR wi ll enable more transparency of ICAO process and allow f or public comment • In addition, this proposal is responsive to the D.C. District Court for the District of Columbia’s 2011 ruling that § 231(a ) imposes a nondiscretionary duty to issue such findings and a 2007 petition requesting that the EPA regulate aircraft GHGs. INTERNAL, DELIBERA TIVE 3

# Approach to Proposed Endangerment Finding under CAA § 231
• Proposal lays out how the legal framework under § 231 is essentially identical to § 202, and that EPA’s interpretation of the CAA under § 202, and EPA’s approach to utilizing the science, have been upheld in court. • The Administrator’s proposed finding for purposes of § 231 is made in light of the evidence, analysis, and conclusions that led to the 2009 Endangerment Finding, as well as more recent evidence.

– Relying primarily on the extensive scientific and technical evidence in the record supporting the 2009 Endangerment Finding under CAA § 202, including the major, peer-reviewed scientific assessments of the IPCC, USGCRP, and NRC.

– Proposal shows we have also considered new assessments released since 2009. These more recent assessments strengthen or provide further support for the science underlying the 2009 Endangerment Finding. 

### • I n proposing this finding for purposes of § 231 , we are not reopening or revising our prior findings under § 202 . INTERNAL, DELIBERA TIVE 4

# Proposed Endangerment Finding under CAA § 231

• Proposing to define the “air pollution” referred to in CAA § 231 to be the mix of six well -mixed GHGs: carbon dioxide (CO2), methane, nitrous oxide, hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF 6).

– This is the same definition that was used for purposes of § 202.

– More recent science continues to support this definition of the air pollution. • Proposing that the total body of scientific evidence compellingly supports a finding that elevated concentrations of the six well -mixed GHGs endanger both the public health and welfare of current and future generations within the meaning of CAA § 231. INTERNAL, DELIBERA TIVE 5

# Proposed Cause or Contribute Finding under CAA § 231

INTERNAL, DELIBERA TIVE 6 

### • Proposing to find that GHG emissions from certain classes of engines used in “covered aircraft”* contribute to the air pollution that endangers public health and welfare.

– * subsonic jet aircraft with a maximum takeof f mass (MTOM) greater than 5,7000 kilograms and subsonic propeller drive aircraft (e.g., turboprops) with a MTOM greater than 8,618 kilograms.

– Proposal lays out how this categorization ensures equivalent scope of applicability as ICAO (see next slide). 

### • As was done under § 202 , our proposal compares U.S. aircraft emissions in both the domestic and global context to demonstrate “contribution.”Larger Transport Jet Larger Tu rboprop Helicopters Military Smaller Tu rboprop 

### Examples of **Aircraft to be**  **Included in ICAO CO** **2** 

### Standard **Examples of Aircraft**  **to be Excluded**  **from ICAO CO 2**  

### Standard ~90% of U.S. GHG emissions from aviation sector ~ 10% of U.S. GHG emissions from aviation sector 

## Proposed **Cause or Contribute Finding**  **under CAA**  § **231**INTERNAL, DELIBERA TIVE 8 • Aircraft sector contributes ~11% of U.S. transportation GHGs

– Largest remaining transportation category not yet regulated for GHGs.

– 3.2% of total U.S. GHG emissions (not pictured). Total transportation is about a third. • The aircraft categories covered by ICAO comprise the vast majority of aviation sector GHG emissions ( U.S. ~ 90%). Source: Inventory of U.S. GHG Emissions and Sinks: 1990-2012 

## Proposed **Cause or Contribute Finding**  **under CAA**  § **231**

## ANPR **Discussion**

• ICAO is expected to finalize CO2 

### standards for aircraft in February 2016.

– FAA serves as the U.S. representative at ICAO, and is active in the CO2 standards development work.

– EPA is also active in the ICAO working groups that are developing the standards. 

### • ICAO standards are not self -implementing, but rather must be implemented through domestic regulation. • EPA, in consultation with FAA, has responsibility for issuing air pollution standards for aircraft engines under CAA § 231.

– We shared drafts of the ANPR with FAA beginning in December, and will continue to work with FAA (and other agencies) during the interagency process. 

### • FAA, under CAA § 232, has responsibility to prescribe regulations to ensure compliance with the emissions standards. INTERNAL, DELIBERATIVE 9

## ANPR **Discussion**
• The ANPR sets the stage for a future proposal for aircraft CO 2 

## standards.

– It is anticipated that this would be the standards finalized by ICAO next year. 

## • Provides an overview on ICAO’s Committee on Aviation Environmental Protection (CAEP) progress to date on establishing aircraft CO2 

## standard.

– Timeline for finalizing in 2016.

– Decisions agreed to thus far by CAEP, such as the metric system and certification procedures for measuring CO2 from aircraft. 

## • Solicits public comment on key aspects of a CO 2 

## standard for aircraft.

– Applicability (new

type vs. in-production)

– Timing and level of standards INTERNAL, DELIBERATIVE 10INTERNAL, DELIBERA TIVE 11 

# Schedule **Milestones Date**  Proposal Signature (following 90 day review) 

### End of May, 2015 CAEP/ICAO Final Aircraft Standards February, 2016 Final Endangerment + Cause or Contribute Rule Spring, 2016