Sierra Club, National Audubon Society and Audubon Arkansas filed a federal lawsuit Thursday against the U.S. Army Corps of Engineers and its district engineer, Jeffrey Eckstein. The suit seeks an injunction to block construction of the $1.6 billion coal-fired plant that Southwestern Electric Power Co. is building in Hempstead County.

The suit accuses the Army Corps of violating the Clean Water Act and other federal environmental laws when it issued a permit to SWEPCO for the plant.

In a separate case, the Arkansas Supreme Court is to hear oral arguments April 15 for SWEPCO's appeal of a ruling that found the state Public Service Commission didn't follow proper procedures before issuing a permit.

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