What was found
STRONG SKUNK SMELL ON DESCENT THRU 5000' PACK 1 OFF ISOLATE SMELL. DESCRIPTION OF ODOR/FUMES: PERSISTENT, MUSTRY DRY/ DIRTY SOCKS SMELL. APPARENT CABIN SOURCE: CABIN AIR SUPPLY VENTS. FLIGHT DECK AND FWD CABIN. NO VISIBLE SMOKE/HAZE. NO MEDICAL ATTENTION REQUIRED.-AS PER TSM 05-50-00-810-831 AND TSM 71-00-00-810-847-A, FOUND ENG 1 AND ENG 2 OVERSRVICED BOTH ENGINES DRAINED TO LIMITS IAW AMM 79-00-00. PERFORMED ECS LEVEL B DECONTAMINATION IAW AMM 21-00-00. R/R RECIRCULATION FILTERS. NO DEFECTS NOTED A/C OK FOR CONTINUED SVC.