As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SLATS FAIL CAUTION MSG ON DESCENT SLAT WOULD NOT EXTEND PAST 0. PERFORMED WATER CONTAMINATION CHECK OF ALL SLAT ACTUATORS PER SL 27-0080, REMOVED WATER FROM LEFT SLAT ACTUATORS 1-1, 2-1 AND RIGHT WING ACTUATORS 1-1, 2-2. RE-INSTALLED ACTUATORS AND OPS CHECKED GOOD PER CRJ-900 AMM # 27-81-09.