The Georgia Department of Transportation will have to backtrack some before it moves forward on the long-proposed Exit 14 project off Interstate 985, officials say. To complete an environmental impact study on the project, officials must restart parts of preliminary engineering, work that’s expected to cost $800,000 — $640,000 from the federal government and $160,000 from the state. Preliminary engineering wrapped up more than seven years ago and “anytime that happens, you need to go back and update some aspects with regards to traffic counts, travel patterns and so forth,” Hall County planner Srikanth Yamala said last week.