# Greenhouse Gas Emissions and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles—Phase 2; Extension of Comment Period
**AGENCY:**
Environmental Protection Agency (EPA) and National Highway Traffic Safety Administration (NHTSA), DOT.
**ACTION:**
Proposed rule; extension of comment period.
**SUMMARY:**
The Environmental Protection Agency (EPA) and the National Highway Traffic Safety Administration (NHTSA) are extending the comment period for the joint proposed rules “Greenhouse Gas Emissions and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles—Phase 2,” and also for NHTSA's Draft Environmental Impact Statement (DEIS). The proposed rules were published in the *Federal Register* on July 13, 2015. The comment period for the proposed rules was to end on September 17, 2015. The DEIS was published to a NHTSA Docket on June 19, 2015, and the comment period for that document was to end on August 31, 2015. The purpose of this action is to extend the comment period for the proposed rules and the DEIS to October 1, 2015.
**DATES:**
The comment period for the proposed rule published July 13, 2015 (80 FR 40139) is extended. Written comments for both documents must be received on or before October 1, 2015.
**ADDRESSES:**
For EPA, direct your comments to Docket number EPA-HQ-OAR-2014-0827. For NHTSA, direct your comments to Docket number NHTSA-2014-0132. For NHTSA's DEIS, direct your comments to Docket number NHTSA-2014-0074. Comments may be submitted using the *www.regulations.gov* Web site, or by mail to the addresses below.
*EPA:* Air and Radiation Docket and Information Center, EPA Docket Center, EPA/DC, EPA WJC West Building, 1301 Constitution Ave. NW., Room 3334, Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air Docket is (202) 566-1742.
*NHTSA:* Docket Management Facility, M-30, U.S. Department of Transportation, West Building, Ground Floor, Rm. W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590. The telephone number for the docket management facility is (202) 366-9324. The docket management facility is open between 9 a.m. and 5 p.m. Eastern Time, Monday through Friday, except Federal Holidays.
**FOR FURTHER INFORMATION CONTACT:**
Questions concerning the NHTSA proposed rule should be addressed to NHTSA: Ryan Hagen or Analiese Marchesseault, Office of Chief Counsel, National Highway Traffic Safety Administration, 1200 New Jersey Avenue SE., Washington, DC 20590. Telephone: (202) 366-2992. Questions concerning the EPA proposed rule should be addressed to EPA: Tad Wysor, Office of Transportation and Air Quality, Assessment and Standards Division (ASD), Environmental Protection Agency, 2000 Traverwood Drive, Ann Arbor, MI 48105; telephone number: (734) 214-4332; fax number: (734) 214-4050; email address: *wysor.tad(at)epa.gov.* You may learn more about the jointly proposed rules by visiting NHTSA's or EPA's Web sites at *http://www.nhtsa.gov/fuel-economy* or *http://www.epa.gov/otaq/climate/regs-heavy-duty.htm* or by searching the rulemaking dockets (NHTSA-2014-0132; EPA-HQ-OAR-2014-0827) at *www.regulations.gov.*
**SUPPLEMENTARY INFORMATION:**
In response to requests for an extension, we are extending the public comment period for the Heavy-Duty Phase 2 Notice of Proposed Rulemaking (80 FR 40139, July 13, 2015; also available in Docket Nos. EPA-HQ-OAR-2014-0827 and NHTSA-2014-0132) to October 1, 2015. As NHTSA published (to Docket No. NHTSA-2014-0074) an accompanying DEIS for NHTSA's proposed rule, we are also extending the comment period for that document to October 1, 2015. This extension will provide the public additional time to provide comment on the proposed rules and DEIS. Both the proposed rules and the DEIS are available at *www.regulations.gov.* Instructions for submitting comments to either EPA or NHTSA are described in the Public Participation section of the Notice of Proposed Rulemaking.
In this joint proposal, there are many issues common to both EPA's and NHTSA's proposals. For the convenience of all parties, comments submitted to the EPA docket will be considered comments submitted to the NHTSA docket, and vice versa. An exception is that comments submitted to the NHTSA docket on NHTSA's (DEIS) will not be considered submitted to the EPA docket. Therefore, the public only needs to submit comments to either one of the two agency dockets, although they may submit comments to both if they so choose. Comments that are submitted for consideration by one agency should be identified as such, and comments that are submitted for consideration by both agencies should be identified as such. Absent such identification, each agency will exercise its best judgment to determine whether a comment is submitted on its proposal.
Dated: August 27, 2015.
Raymond R. Posten,
Associate Administrator for Rulemaking, National Highway Traffic Safety Administration.
Dated: August 31, 2015.
Benjamin Hengst,
Associate Director, Office of Transportation and Air Quality Environmental Protection Agency.