As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT AFTER DEPARTING AT FL 340, DURING DESCENT, RECEIVED A GREEN HYD RESERVOIR LOW LEVEL WARNING. CONFIRMED ON OVERHEAD AND ECAM. FOLLOWED ECAM AND QRH PROCEDURES. MANUALLY EXTENDED LANDING GEAR AND SHUT DOWN APPROPRIATE EQUIPMENT. DECLARED EMERGENCY. ACCOMPLISHED LEAK CHECK IAW TSM FLOW CHART FOR LOW AIR IAW TSM 29-34. FOUND DEPRESSURIZATION VALVE LEAKING AIR. INSTALLED A NEW PRESSURE RELIEF VALVE ON GREEN SYSTEM IAW AMM 29-11-27-04. LEAK CHECKED, NO LEAKS NOTED.