An environmental group wants a federal judge to halt work on a bridge so more study can be done on possible impacts on South Carolina's only national park.
A complaint filed Monday by The Friends of the Congaree Swamp asks U.S. District Judge Margaret Seymour to halt the state Department of Transportation's replacement of the U.S. 601 bridge over the Congaree River.
The road runs just east of Congaree National Park. The group says DOT has violated the National Environmental Policy Act by failing to do enough research on potential effects on the swamp's wetlands.
A Transportation Department spokesman said the agency had not seen the complaint and would not comment.
Construction began this summer and is projected to be finished in 2013.