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Big Stone II Power Plant and Transmission Project, SD and MN, DOE/EIS-0377

Participating utilities announce wind-down of Big Stone II project


The Big Stone II Project participants—Central Minnesota Municipal Power Agency, Heartland Consumers Power District, Missouri River Energy Services and Montana-Dakota Utilities Co.—announced Nov. 2 that they will not build the Big Stone II Project. The project required additional participants to move forward; however none have committed.

Record of Decision issued


On Aug. 24, Western issued its Record of Decision for the Big Stone II Power Plant and Transmission Project Final Environmental Impact Statement. Western considered the environmental impacts of the Project and has decided to allow the request to interconnect at Western’s Morris and Granite Falls substations located in Minnesota. Additionally, an interconnection agreement must be completed in accordance with Western’s Tariff. Western conditions its environmental approval of the Co-owner’s request to interconnect to Western’s transmission system upon the adoption and implementation of the mitigation measures as described in the Final EIS. 

Western received an application to interconnect the BigStone II Power Plant and Transmission Project into Western’s transmission system. The Project entails the construction of a new 600-megawatt coal-fired electric power generating station adjacent to the existing Big Stone plant in Grant County, South Dakota. The Project also includes approximately 140 miles of new or upgraded transmission lines.

Western’s Open Access Transmission Service Tariff provides open access to its transmission system if there is available capacity on the transmission system, while protecting the transmission system reliability, and considering the applicant’s objectives. Western’s Federal involvement is related to the determination of whether to approve the interconnection request for the Project.

About Big Stone II

The Big Stone II Project involves the construction of an approximately 600-MW, coal-fired generating facility near Milbank, in Grant County, S.D. The Big Stone II generating unit would be located next to the existing Big Stone Plant, and would require new or upgraded transmission lines in the area. Two transmission alternatives are proposed in South Dakota and Minnesota. Voltage on the proposed transmission lines would most likely be 230 kV.

Project updates:

Contact information:
NEPA Document Manager
Big Stone II EIS, B0400
Upper Great Plains Region 
Western Area Power Administration
P.O. Box 35800
Billings, MT 59107-5800
1-800-336-7288 or 406-247-7405
Fax: 406-247-7408