The Georgia Ports Authority's (GPA) board yesterday approved $92 million for the Mason Mega Rail Terminal project at the Port of Savannah.The project will double the Port of Savannah's annual rail capacity to 1 million containers. Work approved yesterday includes 124,000 feet of new track, 88 automated switches and rail control devices, as well as the rail and power infrastructure to support the operation of rail-mounted gantry cranes, GPA officials said in a press release.The added rail capacity will better accommodate 10,000-foot long unit trains on Garden City Terminal.