In Reply Refer To:

OEP/DG2E/Gas 2 

Transwestern Pipeline Company, LLC 

Docket No. CP06-459-000 

 

TO THE PARTY ADDRESSED: 

The environmental staffs of the Federal Energy Regulatory Commission (Commission or FERC); the 

U.S. Department of the Interior, Bureau of Land Management (BLM); the U.S. Department of Agriculture, 

Forest Service (FS); the U.S. Department of Transportation, Office of Pipeline Safety (OPS); the U.S. 

Department of the Interior, Bureau of Indian Affairs (BIA); and the Navajo Nation, collectively referred to as 

the Agency Staffs, have prepared this final environmental impact statement (EIS) to address Transwestern 

Pipeline Company, LLC’s (Transwestern) proposed expansion of its natural gas pipeline system. A Final 

General Conformity Determination was also prepared by the FERC to assess the potential air quality impacts 

associated with construction and operation of the proposed Phoenix Expansion Project and is included as 

Appendix Q of this final EIS. 

This final EIS was prepared to satisfy the requirements of the National Environmental Policy Act 

(NEPA). The Agency Staffs have concluded that if the project is constructed and operated in accordance with 

applicable laws and regulations, Transwestern’s proposed mitigation, and the Agency Staffs’ additional 

mitigation measures, it would have limited adverse environmental impact. 

The FERC is the lead federal agency and will use this final EIS to consider the environmental impacts 

that could result if it issues Transwestern a Certificate of Public Convenience and Necessity under section 7 of 

the Natural Gas Act. 

The BLM and the FS are federal land management agencies affected by Transwestern’s proposal and 

have elected to act as cooperating agencies in preparing this final EIS. The BLM will use the document to 

meet its NEPA responsibilities in considering Transwestern’s application for a Right-of-Way Grant and 

obtain Temporary Use Permits for the portion of the project on federal lands under section 185(f) of the 

Mineral Leasing Act of 1920. The BLM would issue the Right-of-Way Grant and Temporary Use Permits for 

the crossing of BLM-managed lands and the Kaibab and Prescott National Forests, which are managed by the 

FS, and for crossing lands managed by the U.S. Department of the Interior, Bureau of Reclamation (BOR). 

The BLM would consider the concurrence or non-concurrence of the FS and BOR, as well as FERC approval 

or denial, in making its decision whether to issue the Right-of-Way Grant and Temporary Use Permits. The 

BLM’s decision would be documented in a Record of Decision. 

The OPS is participating as a cooperating agency in preparing this final EIS because it is responsible 

for ensuring the safe, reliable, and environmentally sound operation of the nation’s transportation system and 

for providing oversight for oil and natural gas pipelines. The OPS' authority is found under the Natural Gas 

Pipeline Safety Act of 1968 (49 USC 1671 et seq.) and the Hazardous Liquids Pipeline Safety Act of 1979 

(49 USC 2001 et seq.). 

The BIA and the Navajo Nation have also elected to act as cooperating agencies in preparing this 

final EIS because the proposed project would be near tribal lands in Arizona and would cross two classes of 
2 

Navajo Nation lands in New Mexico: tribal lands and allotted lands. Tribal lands are owned in fee by the 

Navajo Nation, and access to these lands would be acquired through direct negotiation between Transwestern 

and officials of the Navajo Nation Tribal Headquarters in Window Rock, Arizona. Allotted lands are held in 

trust by the United States government and managed by the BIA for the benefit of individual allottees. 

The Phoenix Expansion Project is designed to transport up to 500 million cubic feet per day of natural 

gas to the Phoenix area, which is one of the fastest-growing regions in the United States. The project would 

not only help to satisfy the increasing demand for electricity and natural gas, but would also increase 

competition in the regional energy market, thereby working to stabilize costs to the consumer. 

This final EIS addresses the potential environmental effects of the construction and operation of the 

following facilities proposed by Transwestern: 

• 24.6 miles of new 36-inch-diameter pipeline loop1

 (the San Juan Lateral Loops A and B) 

extending along the existing San Juan Lateral in San Juan and McKinley Counties, New 

Mexico; 

• 259.3 miles of new 42- and 36-inch-diameter lateral2 pipeline (the Phoenix Lateral), 

consisting of 95.7 miles of 42-inch-diameter pipeline extending from milepost (MP) 0.0 in 

Yavapai County, Arizona to MP 95.2 in Maricopa County, Arizona, and 163.6 miles of 36-

inch-diameter pipeline extending from MP 95.2 in Maricopa County, Arizona to MP 255.1 

in Pinal County, Arizona; 

• 1.4 miles of new 24-, 20-, 16-, and 6-inch-diameter lateral pipeline (the customer laterals) 

connecting the Phoenix Lateral to meter stations that are not located immediately adjacent to 

the Phoenix Lateral right-of-way; 

• minor piping and pressure control modifications at the existing Bloomfield Compressor 

Station in San Juan County, New Mexico and at the existing Seligman Compressor Station 

No. 1 in Mohave County, Arizona; 

• installation of the Ash Fork Facility at MP 0.0 of the Phoenix Lateral in Yavapai County, 

Arizona including 2 filter separators, odorant injection facilities, and telecommunications 

equipment; and 

• installation of 4 taps, 31 valves, 11 meter stations, 6 pig3 launchers, and 3 pig receivers. 

Transwestern would also acquire an undivided interest in the existing East Valley Lateral consisting 

of 36.7 miles of 24-inch-diameter lateral pipeline in Pinal and Maricopa Counties, Arizona. 

 

1

 A loop is a segment of pipeline that is usually installed adjacent to an existing pipeline and connected to it at both ends. The loop allows more gas 

to be moved through the system. 2

 A lateral pipeline typically takes gas from the main system to deliver it to a customer, local distribution system, or another interstate transmission 

system. 3

 A pig is an internal tool that can be used to clean and dry a pipeline and/or to inspect it for damage or corrosion. 
3 

The final EIS, including the Final General Conformity Determination, has been placed in the public 

files of the FERC and is available for distribution and public inspection at: 

Federal Regulatory Energy Commission 

Public Reference Room 

888 First St. NE; Room 2A 

Washington, DC 20426 

(202) 208-1371 

A limited number of copies are available from the FERC’s Public Reference Room identified above. 

These copies may be requested in hard copy or as .pdf files on a CD that can be read by a computer with a 

CD-ROM drive. The final EIS, including the Final General Conformity Determination, is also available for 

viewing on the FERC Internet website at www.ferc.gov. In addition, copies of the document have been 

mailed to federal, state, and local government agencies; elected officials; Native American tribes; affected 

landowners; local libraries and newspapers; intervenors to the FERC’s proceeding; and other interested 

parties. Hard copies of the final EIS, including the Final General Conformity Determination, can be viewed 

at the following libraries in the project area: 

Ash Fork Public Library 

518 Lewis Avenue 

Ash Fork, AZ 86320 

Avondale-Goodyear Public Library

328 West Western Avenue 

Avondale, AZ 85323 

Black Canyon City Community Library

34701 South Old Black Canyon Hwy 

Black Canyon, AZ 85324 

Buckeye Public Library 

310 North 6th Street 

Buckeye, AZ 85032 

Casa Grande Public Library 

449 North Dry Lake 

Casa Grande, AZ 85222 

Chino Valley Public Library 

1020 West Palomino Road 

Chino Valley, AZ 86323 

Coolidge Public Library 

160 West Central Avenue 

Coolidge, AZ 85228 

Flagstaff Public Library 

300 West Aspen 

Flagstaff, AZ 86001 

Fredonia Public Library 

118 North Main Street 

Fredonia, AZ 86022 

Mayer Public Library 

10004 Wicks Street 

Mayer, AZ 86333 

Arizona State Library 

1700 West Washington Street 

Phoenix, AZ 85007 

North Central Regional Library 

17811 North 32nd Street 

Phoenix, AZ 85032 

Yavapai County Library District 

172 East Merritt Street, Suite E 

Prescott, AZ 86301 

Prescott Public Library 

215 East Goodwin 

Prescott, AZ 86303 

Prescott Valley Public Library 

7501 East Civic Circle 

Prescott Valley, AZ 86314 

Williams Public Library 

113 South First Street 

Williams, AZ 86046 

Bloomfield Public Library 

333 South First Street 

Bloomfield, NM 87413 

Farmington Public Library 

2101 Farmington Avenue 

Farmington, NM 87401-6420 

Octavia Fellin Public Library 

115 West Hill 

Gallup, NM 87301 

 

Additional information about the project is available from the Commission’s Office of External 

Affairs at 1-866-208-FERC or on the FERC Internet website (www.ferc.gov) using the eLibrary link. Click 

on the eLibrary link, click on “General Search,” and enter the docket number excluding the last three digits in 

the Docket Number field. Be sure you have selected an appropriate date range. For assistance, please contact 

FERC Online Support at FERCOnlineSupport@ferc.gov or toll free at 1-866-208-3676, or for TTY, contact 

(202) 502-8659. The eLibrary link on the FERC Internet website also provides access to the texts of formal 

documents issued by the Commission, such as orders, notices, and rulemakings. 
4 

 In addition, the Commission now offers a free service called eSubscription that allows you to keep 

track of all formal issuances and submittals in specific dockets. This can reduce the amount of time you 

spend researching proceedings by automatically providing you with notification of these filings, document 

summaries, and direct links to the documents. To register for this service, go to the eSubscription link on the 

FERC Internet website. 

 Information concerning the involvement of the cooperating agencies in the EIS process may be 

obtained from: 

U.S. Department of the Interior, 

Bureau of Land Management 

Mark Mackiewicz, (435) 636-3616 

U.S. Department of Agriculture, 

Forest Service 

Prescott National Forest 

Vicki Clay, (928) 443-8013 

Kaibab National Forest 

Tom Mutz, (928) 635-5661 

U.S. Department of Transportation, 

Office of Pipeline Safety 

Ross Reineke, (720) 963-3182 

U.S. Department of the Interior, 

Bureau of Indian Affairs 

Navajo Area Office 

Harrilene Yazzi, (505) 863-8286 

Phoenix Area Office 

Amy Heuslein, (602) 379-6750 

Navajo Nation 

Ron Maldonado, (928) 871-7139 

Kimberly D. Bose 

Secretary