What was found
(CAN) WHEN THE CREW EXTENDED THE LANDING GEAR THE REPORTED A GREEN HYDRAULIC SYS LOW PRESSURE CONDITION. CHECK LIST FOLLOWED AND LANDING CARRIED OUT. EMERGENCY DECLARED WITH ATC, DID NOT DECLARE MAYDAY OR PANPAN. LT MLG ACTUATOR AFT HYDRAULIC LINE REPLACED IAW AMM 20-21-12, PB 201 AND HYD PTU REPLACED IAW AMM 29-23-41, PB 401.