An environmentalist group is urging state officials to reject plans for a multistate power line that would run through northern Virginia.

In a brief filed this week with the State Corporation Commission, the Piedmont Environmental Council argues against the $1.3 billion Trans-Allegheny Interstate Line, proposed by Dominion and Pennsylvania-based Allegheny Energy. The 500-kilovolt transmission line would run 240 miles from Washington County, Pennsylvania, to Loudoun County, Virginia.

The group urges the commission to reject the application on the grounds that the powerline isn't necessary and that simpler alternatives exist to meet power needs in northern Virginia.

Dominion says the power line is needed to satisfy the growing demand for electricity and could help avoid blackouts expected to start in 2011.