What was found
***WHILE A/C WAS OUT OF SERVICE FOR HEAVY CHECK*** CENTER FUSELAGE III UNDER CABIN FLOOR, CORROSION FOUND ON WASTE BOX BTW FR 88-89 AND BTW STR 26R-28R. CENTER FUSELAGE III UNDER CABIN FLOOR BTW FR 88-89 AND BTW STR 26R-28R, WASTE BOX REPLACED IAW SRM 51-43-04, PSE 53-23-018. A/C REMAINS OUT OF SERVICE FOR HEAVY CHECK COMPLETION.