ST. PAUL, Minn. (AP) - Minnesota regulators have issued their final written order for transmission lines for the proposed $1.6 billion Big Stone II coal power plant in South Dakota.

In January, the Minnesota Public Utilities Commission unanimously approved the lines for west-central Minnesota, with conditions.

Otter Tail Power Co. and four other utilities are planning the 500-megawatt coal-fired plant for the Milbank area of northeastern South Dakota.

Project manager Mark Rolfes says the order gives the group "a firmer understanding on which to continue our planning."

Rolfes says the project continues to make preliminary plans for construction to begin in late 2010.

The U.S. Environmental Protection Agency has filed objections to an air quality permit a South Dakota agency had granted for the project. South Dakota has until April 22 to respond.

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