ANDERSON — A Seneca firefighter died when the tractor-trailer rig he was driving blew a tire and ran off a bridge over Lake Hartwell in Anderson County.Coroner Greg Shore said 49-year-old David Ray Wright was under water for about half an hour Monday night before divers got to him. He was taken to AnMed Health Medical Center in Anderson where he was pronounced dead. Wright was also a volunteer fire chief in Oconee County.Shore said Wright was helping his father, who delivers mobile homes. Wright was driving the rig when it ran off the state Highway 24 bridge. Another man in the truck suffered only minor injuries. Wright had been with the Seneca Fire Department nearly 24 years. He had worked with the Oconee County Fire Department about 35 years.