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Environmental Impact Statements (EISs)

FERC issues Final Environmental Impact Statement on Rockies Western Phase Project (Docket Nos. CP06-354-000, CP06-401-000, and CP06-423-000)
Issued: March 16, 2007

The staff of the Federal Energy Regulatory Commission (Commission or FERC), has prepared a final environmental impact statement (EIS) on the natural gas pipeline facilities proposed by Rockies Express Pipeline LLC (Rockies Express), TransColorado Gas Transmission Company (TransColorado), and Questar Overthrust Pipeline Company (Overthrust) in the above-referenced dockets. The Rockies Western Phase Project (Project) would consist of the construction and operation of approximately 795.6 miles of natural gas pipeline and a total of 237,320 horsepower of new compression. Following completion of the proposed facilities, the Project would transport up to 1.5 billion cubic feet of natural gas per day.

As a part of its REX-West Project, Rockies Express proposes to construct and operate approximately 712.7 miles of 42-inch-diameter natural gas pipeline in various counties in Colorado, Wyoming, Nebraska, Kansas, and Missouri and about 5.3 miles of 24-inch-diameter pipeline lateral in Sweetwater and Carbon Counties, Wyoming. Rockies Express also proposes to construct five new compressor stations (in Weld and Sedgwick Counties, Colorado; Sweetwater County, Wyoming; Gage County, Nebraska; and Clinton County, Missouri), and install additional compression at two existing stations (in Rio Blanco County, Colorado and Sweetwater County).

As a part of its Blanco to Meeker Project, TransColorado proposes to install about 1,300 feet of 24-inch-diameter pipeline and 60 feet of 16-inch-diameter pipeline in San Juan County, New Mexico. TransColorado also proposes to construct two new compressor stations (in Garfield County, Colorado and San Juan County) and install additional compression at an existing station in Rio Blanco County.

As a part of its Wamsutter Expansion Project, Overthrust proposes to construct and operate approximately 77.2 miles of 36-inch-diameter natural gas pipeline in Sweetwater County, Wyoming. Overthrust also proposes to construct two new compressor stations in Wyoming (Lincoln and Sweetwater Counties).

All three applicants would construct appurtenant facilities, such as valves, meter stations, tie-ins, and minor compressor station modifications and station piping.

The final EIS was prepared to satisfy the requirements of the National Environmental Policy Act and the Federal Land Management and Policy Act. The U.S. Bureau of Land Management (BLM) and U.S. Fish and Wildlife Service (FWS) are participating as cooperating agencies in the preparation of the EIS.

The FERC staff concludes that the proposed Project, with the appropriate mitigation measures as recommended, would be an environmentally acceptable action. The principal reasons are:

    • More than 99 percent of the REX-West facilities would be collocated with existing rights-of-way, while the Wamsutter Expansion Project would parallel existing rights-of-way for its entire length;

    • The Project would be consistent with or in conformance with federal resource management plans;

    • The applicants would implement resource- or activity-specific plans, procedures, and agreements to protect natural resources, avoid or limit environmental impact, and promote restoration of all disturbed areas during construction and operation of the Project;

    • Rockies Express would use an Agricultural Inspector knowledgeable in plains and midwestern farming practices, who would provide input and guidance during construction in agricultural areas;

    • Rockies Express has developed Depth of Cover and Terrace Construction/Repair Plans that, along with our recommended revisions to these plans, would ensure that site-specific farming practices and related landowner concerns are met;

    • The use of the horizontal directional drill method would avoid disturbances to the beds and banks of the Missouri River, Big Creek, Little Blue River, and Deadman Wash;

    • The appropriate consultations with the State Historic Preservation Officers, FWS, BLM, other affected land management agencies, and any appropriate compliance actions resulting from these consultations, would be completed before the applicants would be allowed to begin construction in any given area; and

    • An environmental inspection and monitoring program would be implemented to ensure compliance with all mitigation measures, Certificate conditions, requirements contained in the BLM's Plan of Development, and other stipulations included in permits from other authorizing federal, state, and local agencies.

    FERC Commissioners will take into consideration staff's recommendations and the final EIS when they make a decision on the project.