What was found
ON DESCENT, EICAS MESSAGE HYD 2 LO QTY. CHECKED HYDRAULIC PAGE ON MFD AND NOTICED QUANTITY WAS RAPIDLY DECREASING FROM APPROX 12 PERCENT DOWN TO 0 PERCENT. ONCE THE QUANTITY REACHED 0 PERCENT THE PRESSURE STARTED TO DECREASE FROM 3000 PSI DOWN TO 0 PSI, THEN HYD 2 LO PRESS EICAS MESSAGE APPEARED. FOLLOWED QRH, DECLARED EMERGENCY, LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED A SUPPORT ASSY AND NIPPLE ON SUPPLY LINE NR 2 IAW GE IPC 71-00-05. OPS AND LEAK CHECK GOOD.