An A319 flight crew managed a near complete Green System Hydraulic failure.

Narrative

ECAM's Displayed: -HYD GREEN SYSTEM LO PRESSURE -PTU OFF -GREEN HYD ENGINE PUMP OFF We get ECAM warnings while still at level flight. Captain is flying. First Officer checks back of QRH for Immediate Actions and ECAM exceptions for HYD GREEN SYSTEM LO PRESSURE. Not listed. Captain calls for ECAM Actions. We turn off PTU and Green Hydraulic engine pump and check HYD page. We note the Green quantity is very low and almost to the amber level at the bottom of the quantity gauge. Yellow and Blue quantities are still full. We suspect a Green hydraulic leak or an indication problem with the Green system. We note all inoperative systems on system status page. Flying duties are assigned to the First Officer and the Captain starts looking up problem in QRH. Captain is reading QRH out loud and First Officer is handling the radios and flying the plane. I can hear the Captain say Configuration 3; Gravity Gear extension and landing distance additions. ATC now says cleared direct XXXXX and cross at 12;000 / 250 knots. Captain declares an emergency with ATC and advises of our problem and intentions of landing 36C; requesting the emergency equipment standing by. Captain ACARS's company; calls lead Flight Attendant and informs him of the emergency; and directs him to prep the cabin for a normal landing and explains the gravity extension of the landing gear and tow off the runway because of no nose wheel steering. Captain then uses PA to inform passengers that we declared an emergency; one of our hydraulic systems has a problem; and that we are planning a normal landing but will need to be towed off the runway. He also mentions that as a precaution; they will see flashing red lights from emergency vehicles standing by. First Officer informs ATC that our nose wheel steering is inoperative and we will need to be towed off runway. First Officer gets current ATIS and sets up for ILS 36C; configuration 3. We discuss what the QRH says and review inoperative systems on the status page. Runway distance calculations are applied and note we have enough runway to land. Captain informs ATC again that we want 36C; and requests a long down wind and base turn so we have time to configure with the gravity gear extension. We talked about having the First Officer fly the approach and Captain doing the manual gear extension since he read the QRH and then agreed the Captain will later land the aircraft. First Officer calls for descent and approach checklists. On base turn Captain checks Green hydraulic level. The Green level is noted above the Amber level and Captain informs First Officer that the QRH allows one last try to extend gear with the normal Green system on. We put the Green system engine hydraulic pump and PTU back on. No additional ECAM warning. Landing gear comes down. First Officer calls for flaps 3; landing checklists. After checklist complete I ask the Captain if he is ready to take over flying the aircraft. We transfer controls. Landing was normal and we were able to clear the runway on our own. Captain tells First Officer to inform ATC we are cancelling our emergency status. ATC asks if there might be hydraulic fluid on runway. We told them we did not know. Ramp is called and we taxi to our gate. First Officer calls Maintenance to inform them of our low Green hydraulic quantity and asks them to meet us at the gate. First Officer uses PA to inform passengers that the emergency is cancelled and we will be taxing to the gate normally. Mechanic meets us at the gate and informs us that he did notice hydraulic fluid leaking from our plane.