What was found
(CAN) ON TAKEOFF THE CREW WAS INFORMED BY BOTH ATC AND A FOLLOWING AIRCRAFT OF FUEL LEAKING FROM THE LEFT WING. AIRCRAFT RETURNED TO THE DEPARTURE AIRPORT AND CARRIED OUT AN UNEVENTFUL LANDING. UPON INVESTIGATION BY MAINTENANCE PERSONNEL IT WAS DISCOVERED THAT THE SURGE BAY WAS FULL OF FUEL. FUEL WAS TRANSFERRED TO THE CENTRE TANK TO ALLOW THE SURGE TANK TO DRAIN AND REDISTRIBUTE THE FUEL LOAD. OVERFUELING BY GROUND PERSONNEL IS SUSPECTED AS THE CAUSE OF THIS EVENT.