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Draft Guidance for E85 Flexible Fuel Vehicle Weighting Factor for Model Years 2016-2019 Vehicles Under the Light-Duty Greenhouse Gas Emissions Program

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Environmental Protection Agency (EPA).




EPA is requesting comment on draft EPA guidance to auto manufacturers for weighting the greenhouse gas (GHG) emissions of a flexible fuel vehicle operating on E85 with the GHG emissions of the vehicle operating on conventional gasoline, when calculating the compliance value to use for EPA's GHG emissions standards. EPA also invites comment on the analysis used by EPA to determine the weighting factor.


Comments must be received on or before April 22, 2013.


Submit your comments, identified by Docket ID No. EPA-HQ- OAR-2013-0120, by one of the following methods:

  • On-Line at Follow the On- Line Instructions for Submitting Comments.
  • Email:
  • Fax: (202) 566-1741.
  • Mail: Air and Radiation Docket, Docket ID No. EPA-HQ-OAR-2013- 0120, U.S. Environmental Protection Agency, Mailcode: 6102T, 1200 Pennsylvania Avenue NW., Washington, DC 20460. Please include a total of two copies.
  • Hand Delivery: EPA Docket Center, Public Reading Room, EPA West Building, Room 3334, 1301 Constitution Avenue NW., Washington, DC 20460. Such deliveries are only accepted during the Docket's normal hours of operation, and special arrangements should be made for deliveries of boxed information.

On-Line Instructions for Submitting Comments: Direct your comments to Docket ID No. EPA-HQ-OAR-2013- 0120. EPA's policy is that all comments received will be included in the public docket without change and may be made available online at, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through or email.

The Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an email comment directly to EPA without going through, your email address will automatically be captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses. For additional information about EPA's public docket visit the EPA Docket Center homepage at​epahome/​dockets.htm.

Materials relevant to this proceeding are contained in the Air and Radiation Docket and Information Center, maintained in Docket ID No. EPA-HQ- OAR-2013-0120. Publicly available docket materials are available either electronically through or in hard copy at the Air and Radiation Docket in the EPA Headquarters Library, EPA West Building, Room 3334, located at 1301 Constitution Avenue NW., Washington, DC. The Public Reading Room is open to the public on all federal government work days from 8:30 a.m. to 4:30 p.m.; generally, it is open Monday through Friday, excluding holidays. The telephone number for the Reading Room is (202) 566-1744. The Air and Radiation Docket and Information Center's Web site is​oar/​docket.html. The electronic mail (email) address for the Air and Radiation Docket is:, the telephone number is (202) 566-1742, and the fax number is (202) 566-9744. An electronic version of the public docket is available through the federal government's electronic public docket and comment system. You may access EPA dockets at After opening the Web site, enter EPA-HQ-OAR-2013-0120 in the “Enter Keyword or ID” fill-in box to view documents in the record. Although a part of the official docket, the public docket does not include Confidential Business Information (CBI) or other information whose disclosure is restricted by statute.

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Roberts French, Environmental Protection Specialist, Office of Transportation and Air Quality, Compliance Division, U.S. Environmental Protection Agency, 2000 Traverwood Drive, Ann Arbor, MI 48105. Telephone: (734) 214-4380. Fax: (734) 214-4869. Email address:

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I. Background

Under EPA's greenhouse gas (GHG) program for passenger automobiles and light trucks, starting with the 2016 model year, the regulations describe two pathways for determining the GHG value for flexible fuel vehicles (FFVs) that run either on gasoline or on E85 (a fuel mixture of 85 percent ethanol and 15 percent gasoline). The default approach is to use the GHG emissions of the vehicle operated solely on gasoline (see 40 CFR 600.510-12). The alternative is to combine the gasoline and E85 GHG values together in a way that accounts for real-world use of E85 by using a weighting factor.[1] When the weighting factor is used, the emissions value used for the vehicle model in the fleet average calculations would be determined by weighting the gasoline and E85 values of the model together using the specified factor (see 40 CFR 600.510-12(k)).

EPA's regulations establish two different approaches that may be used to determine the value of the weighting factor. Manufacturers may request that EPA determine and publish by guidance an appropriate value for the E85 weighting factor based on EPA's assessment of the real-world use of E85. Alternatively, a manufacturer may Start Printed Page 17661submit data demonstrating the actual real-world use of E85 by its vehicles. EPA would determine whether the data is adequate and what an appropriate weighting factor should be for the manufacturer.

In mid-2012, manufacturers requested that EPA provide a weighting factor to use for 2016 and later model year vehicles. EPA has assessed the weighting factor that would be appropriate to use and intends to issue guidance to vehicle manufacturers regarding the E85 weighting factor (called the F factor) that may be used by manufacturers for weighting the CO2 of FFVs using E85 and conventional gasoline. EPA intends to establish the weighting factor for the 2016 model year. The weighting factor may also be used for the 2017-2019 model years unless EPA takes action to revise the factor for the later model years based on new information or data.

EPA seeks input by the public prior to our issuing final F factor guidance, and requests comment on the value that we have determined and on the methodology used to derive this value. We have placed a draft guidance letter, including a support document attachment that provides additional background and describes the methodology used by EPA to determine the weighting factor, in the EPA Air Docket EPA-HQ-OAR-2013-0120 and available at​otaq/​regs/​ld-hwy/​greenhouse/​ld-ghg.htm. The draft guidance letter provides for use of a weighting factor of 0.2.

Interested parties should submit comments according to the guidelines described in this notice. After fully considering the comments we receive, we will issue a final guidance document.

II. Procedures for Public Participation

EPA will keep the record open until April 22, 2013. All information will be available for inspection at the EPA Air Docket No. EPA-HQ-OAR-2013-0120. Persons with comments containing proprietary information must distinguish such information from other comments to the greatest extent possible and label it as “Confidential Business Information” (“CBI”). If a person making comments wants EPA to base its decision on a submission labeled as CBI, then a non-confidential version of the document that summarizes the key data or information should be submitted to the public docket. To ensure that proprietary information is not inadvertently placed in the public docket, submissions containing such information should be sent directly to the contact person listed above and not to the public docket. Information covered by a claim of confidentiality will be disclosed by EPA only to the extent allowed, and according to the procedures set forth in 40 CFR part 2. If no claim of confidentiality accompanies the submission when EPA receives it, EPA will make it available to the public without further notice to the person making comments.

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Dated: March 15, 2013.

Christopher Grundler,

Director, Office of Transportation and Air Quality, Office of Air and Radiation.

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1.  The tailpipe GHG emissions used for compliance with the CO2 standards described in 40 CFR 86.1818 are the carbon-containing emissions (generally, CO2, hydrocarbons, and carbon monoxide), which are summed based on the carbon weight fraction of each component into a value described in the regulations as the “carbon-related exhaust emissions” (CREE). For simplicity, however, in this notice we are using the term CO2 instead of CREE, as CO2 is more broadly understood and makes up the vast majority of the total carbon emissions from vehicles.

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[FR Doc. 2013-06657 Filed 3-21-13; 8:45 am]