Black Hills Power, Inc.

Basin Electric Power Cooperative and Powder River Energy Corporation

Common Use System Transmission

GENERAL INFORMATION

The Common Use System (“CUS”) consists of transmission facilities owned and operated by Black Hills Power, Inc., Basin Electric Power Cooperative, and Powder River Energy Corporation (each “Transmission Provider”, collectively “Transmission Providers”) in the south western area of South Dakota and the north eastern portion of Wyoming. Black Hills Power is the administrator of the CUS Joint Open-Access Transmission Tariff (“Joint Tariff”). The owners of the CUS have entered into an agreement with Western Area Power Administration, Rocky Mountain Region, which operates the WACM Control Area, to act as their designated agent for posting Available Transmission Capacity (“ATC”) and administering the OASIS. WACM will process requests for short-term transmission service on the CUS and Black Hills, as tariff administrator, will process requests for long-term transmission service.

WACM Contact Information:

Bob Easton: Transmission Planning and Operations Engineering

Phone: (970) 461-7379

E-mail: aeaston@wapa.gov

Paul Humberson: Transmission Scheduling and Security

Phone: (970) 461-7327

E-mail: humber@wapa.gov

Raymond Vojdani: OASIS Administrator & Security Officer

Phone: (970) 461-7379

E-mail: avojdani@wapa.gov

Black Hills Contact Information:

Michael J. Fredrich: Director of Transmission

Phone: (605) 721-2273

E-mail: mfredrich@bh-power.com