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SunZia Southwest Transmission Project

SunZia Update: BLM Initiates Environmental Assessment to Address Transmission Line Burial North of White Sands Missile Range

The Bureau of Land Management (BLM) is preparing an Environmental Assessment (EA) for the SunZia Southwest Transmission Project (SunZia) to determine whether newly identified measures to mitigate potential impacts to military operations require the BLM to prepare a supplement to the Final Environmental Impact Statement (EIS) published in June 2013.  On June 4, 2014, the Department of Defense (DoD) offered mitigation measures that, if adopted, would address DoD’s prior objections to the SunZia project by resolving potential impacts to military operations.  Most notably, DoD identified as mitigation the proposed burial of a total of approximately five miles of the BLM’s preferred alternative route for the SunZia project in up to three separate segments north of White Sands Missile Range (WSMR) within an area known as the “call-up area.” 
Pursuant to 40 C.F.R. § 1501.3(b), a federal agency has broad discretion to “prepare an environmental assessment on any action at any time in order to assist agency planning and decision-making.”  In this instance, the BLM will undertake an EA to examine whether DoD’s proposed mitigation measures represent “substantial changes in the proposed action that are relevant to environmental concerns” or present “significant new circumstances or information relevant to environmental concerns and bearing on the proposed action or its impacts” from what the BLM analyzed in the Final EIS, which would require the BLM to prepare a supplemental EIS pursuant to 40 C.F.R. § 1502.9(c)(1).  The EA’s scope will be limited to analyzing the impacts of DoD’s mitigation proposal to burying three short segments totaling approximately five miles of the transmission line along BLM’s preferred alternative route within the call-up area.  

The BLM expects to publish the Draft EA in Fall 2014, with a Final/Approved EA expected in late 2014 or early 2015. 

Final Environmental Impact Statement and Proposed Resource Management Plan Amendments (FEIS/RMPA) document for the SunZia Southwest Transmission Project. This Final EIS includes responses to comments received on the Draft EIS, corrects and adds information obtained after preparation of the Draft EIS, and identifies the Bureau of Land Management (BLM) preferred alternative for the Project. The Final EIS is a complete assessment of the environmental impacts of the proposed action and route alternatives, and includes an analysis of the No Action alternative.

The Notice of Availability (NOA) for this FEIS/RMPA was published in the Federal Register by the Environmental Protection Agency (EPA) and the BLM on June 14, 2013. Publication of the NOA was followed by a 30-day protest period on the proposed RMPA relative to this final EIS that ended July 14, 2013, and a Governor's Consistency Review.

For more information on the protest process and regulations 43 CFR 1610.5-2, or online at

Project Background

The BLM is the lead federal agency for the development of the EIS/RMPA for the proposed SunZia Southwest Transmission Project that is being conducted pursuant to the National Environmental Policy Act (NEPA), Federal Land Policy and Management Act, and associated regulations.

Cooperating agencies participating in the development of the EIS/RMPA include: Arizona Department of Transportation, Arizona State Land Department, Arizona Game and Fish Department, National Park Service, New Mexico Spaceport Authority, New Mexico State Land Office, U.S. Army Corps of Engineers, Holloman Air Force Base, Ft. Bliss (U.S. Army), White Sands Missile Range (U.S. Army), Ft. Huachuca (U.S. Army), U.S. Fish and Wildlife Service, the Department of Defense Siting Clearinghouse, and the Bureau of Indian Affairs. Consultation has included other federal agencies and local, state, and tribal governments.

This project is proposed by SunZia Transmission, LLC. The company plans to construct and operate two 500 kilovolt (kV) transmission lines originating at a new substation in Lincoln County in the vicinity of Corona, New Mexico, and terminating at the Pinal Central Substation in Pinal County near Coolidge, Arizona.

The purpose of the proposed Project is to transport electricity generated by power generation resources, including renewable resources, to western power markets and load centers. The Project would enable the development of renewable energy resources including wind, solar, and geothermal generation by creating access to the interstate power grid in the Southwest.

Release of this Final EIS/RMPA follows an extensive public involvement process initiated by the BLM in 2009 to identify relevant issues and concerns. A 90-day comment period followed the release of the Draft EIS in May of 2012. In consideration of public input and analyzing the consequences of the Project proposal, the BLM has identified a preferred alternative, approximately 515 miles in length.  It is estimated that approximately 185 miles, or 36 percent of the right-of-way for the BLM preferred alternative, would be located on federally administered lands in New Mexico and Arizona.  To the extent feasible and practicable, the proposed SunZia Project transmission lines would be located along existing transmission line corridors and designated utility corridors on federal land. 

Two plan amendments are needed in order for the preferred route to be consistent with the BLM’s Socorro RMP (2010, Socorro Field Office) and Mimbres RMP (1993, Las Cruces District Office). The plan amendments include proposed modifications to visual resource management objectives and right-of-way avoidance area management.

 Photo of Windmills

News and Announcements

May 27, 2014 Letter from Secretary Hagel to Secretary Jewell

News Releases,  Announcements and Notices

Notice of Availability of the Final Environmental Impact Statement for the SunZia Southwest Transmission Project in New Mexico and Arizona and Proposed Resource Management Plan Amendments

Environmental Protection Agency Publication: Notice of Availability for the Final EIS and Proposed RMP Amendments for the SunZia Southwest Transmission Project, June 14, 2013


Draft EIS/RMPA - May 2012
Volume I-Draft EIS/RMPA 
Volume II-Appx. A-C 
Volume III-Appx D-H

Preliminary Plan of Development - Draft June 2012

Scoping Report - April 2010

A Citizen's Guide to the NEPA

SunZia Alternative Links, Subroutes and Routes .kml (requires Google Earth or other compatible GIS application to view)
Western Renewable Energy Zones (WREZ) Qualified Resource Areas

Disclaimer statement to newsletters below)
Newsletter 5, June 2013
Newsletter 4, June 2012
Newsletter 3, April 2010
Newsletter 2, October 2009
Newsletter 1, May 2009


Adrian Garcia  

Bureau of Land Management
SunZia Transmission Line Project
P.O. Box 27115
Santa Fe, NM 87502-0115