The authority also asked a judge to block South Carolina's Savannah River Maritime Commission from entering the suit, saying that would expand the action and simply bring in extraneous issues.
The authority wants the river shipping channel deepened to handle larger ships that will be routinely calling when the Panama Canal is deepened in 2014. It filed the motions on Wednesday and U.S. District Judge Richard Gergel on Thursday gave the other parties in the case until Aug. 6 to respond.
The lawsuit filed by environmental groups contends the U.S. Army Corps of Engineers needs a South Carolina pollution permit before the deepening work can begin. The suit alleges toxic cadmium from river silt will be dumped in a dredge spoils area on the South Carolina side of the river.
The suit was brought by the Southern Environmental Law Center on behalf of the Savannah Riverkeeper, based in Augusta, Ga., as well as the South Carolina Coastal Conservation League and the South Carolina Wildlife Federation.
The motion says the Georgia Ports Authority has the right to enter the lawsuit and if not permitted to do so "its ability to protect its interests could be impaired because the environmental groups and the Maritime Commission, if it is permitted to intervene, seek to alter, delay and/or stop" the river deepening.
In answering the lawsuit itself, attorneys wrote that while there will be naturally occurring cadmium in the dredged material, "no adverse impacts" will occur.
The South Carolina Maritime Commission should be blocked from the case because it "will be burdening the parties with extraneous issues," the motion said, adding that letting the commission in "would have parties stake out positions and advance arguments concerning the commission's own authority which may ultimately be determined by the South Carolina Supreme Court."
If the commission is allowed as a party, it should only be able to address the permit issue before the court, the motion said.
The commission, in seeking to enter the case, wants Gergel to rule that in the deepening project, the Corps of Engineers must obey South Carolina environmental rules and "must comply with South Carolina law, including orders, rulings, decisions, and opinions" of the state's Supreme Court, Administrative Law Court and the commission.
Environmentalists have also sued in state court, alleging a water quality permit for the deepening approved by the Department of Health and Environmental Control last year is illegal because the commission, not DHEC, has authority over activities on the river.
The state Supreme Court has not yet ruled in that case but Chief Justice Jean Toal said during a hearing that DHEC broke state law when it left the commission out of dredging negotiations and "rubber stamped" an agreement with Georgia officials.