What was found
FLT 76, BDL-LAX. INFLIGHT REPORTED THAT THEY SMELLED THE DIRTY SOCK SMELL DURING DESCENT AROUND 2K FT. INTENSITY WAS STRONG ONLY IN REAR OF ACFT THERE WAS A FAINT ODOR IN COCKPIT ON THE FINAL APPROACH. ACCOMPLISHED STAGE 1 ECS DECONTAMINATION LEVEL C IAW AMM 21-00-00-941-064A. THROUGH COMPLETION OF 21-00-00-860-124A. WITH NO FAULTS FOUND AFTER. ACFT CONFIGURED FOR LEVEL C STAGE 2. R & R OIL FILTER DIFFERENTIAL PRESSURE SWITCH IAW AMM 49-91-14 PB 401. NO LEAKS NOTED DURING APU OPS. ACCOMPLISHED STAGE 2 CLEANING OF THE ECS PER AMM 21-00-00-160-199-A W/ NO SMOKE OR STRONG ODORS DETECTED BLEED SOURCE APU AND BOTH ENGINES.