What was found
AIRCRAFT WAS NOT GROUNDED: AIRCRAFT HOLDING SHORT OF DEPARTING RUNWAY REPORTED FUEL MIST UPON ROLLOUT. OBSERVED FUEL OF LEFT MAIN 8.35 AND RIGHT MAIN 8.51FOLLOWED QRH FUEL LEAK PROCEDURE. NOTICED 500LB IMBALANCE WITHIN 30 MINUTES. DECIDED TO RETURN TO DFW. EMERGENCY WAS DECLARED AND ACFT LANDED OVERWEIGHT WITHOUT INCIDENT. MAINTENANCE ACCOMPLISH WALK AROUND OF AIRCRAFT FOUND NO DEFECTS ON THE GROUND. CHECKED BOTH ENGINES PER AMM 71-00-00 NO LEAKS NOTED FROM VENTS. ACCOMPLISHED VISUAL INSPECTION BOTH WINGS NO LEAKS NOTED IAW AMM 28-10-00. NO IMBALANCE ALERT CAME UP ON CAPT DISPLAY AS PER FIM28-10-00.