Neither the Army Corps of Engineers nor Southern Nuclear wants to pay for dredging portions of the Savannah River to allow barges to move new reactor parts to Plant Vogtle.

"They had talked before about wanting the corps to maintain the channel with federal money, and we informed them we didn't have any," said Bill Bailey, the chief of the corps' Savannah Planning Unit.

As part of the plan to add two new reactors to Plant Vogtle, located 110 river miles from the coast, the plant's parent company is exploring the use of barges to haul large components upstream.

Beth Thomas, a company spokeswoman, said the Westinghouse Shaw Consortium continues to evaluate other options -- including rail or highways -- and has not made a decision.

"If dredging is used, only a small portion of the river would require dredging," she said. "By small, we mean six to eight miles of the 110-mile channel."

The largest parts are steam generators -- weighing 600 to 800 tons apiece. Two generators will be needed for each new reactor.

For decades, the corps dredged and maintained a 9-foot-deep, 90-foot-wide shipping channel from Savannah to Augusta, but such maintenance ended in 1979, when the last commercial shipping companies ceased operations.

Col. Edward Kertis, the corps' Savannah District commander, wrote in response to an inquiry from Friends of the Earth that such work would require congressional approval.

"To date, Congress has not appropriated sufficient funds to perform maintenance dredging," he wrote. "If Southern Company or any other private entity proposed to conduct the work independently, then they would be responsible for all costs associated with such a project."

Ms. Thomas estimates that the first shipments requiring special transportation would be in spring 2012.