As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE CLIMBING THROUGH 4,000FT, THE FLIGHT CREW WAS NOTIFIED OF FUEL LEAKING FROM THE LEFT WING. THE AIRCRAFT RETURNED TO ATL AND LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE LEFT FUEL VENT FLOAT VALVE LEAKING. THE LEFT FUEL VENT FLOAT VALVE WAS REPLACED WITH NO FURTHER DEFECTS NOTED.