As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT WING AFT SPAR AT LEFT DEFUEL ADAPTER PLATE CORROSION WAS DISCOVERED WHEN CHECKING BONDING OF ADAPTOR PLATE TO WING. REMOVED CORROSION BY SPOT FACING AREA. PERFORMED NDT AND, VISUAL INSP TO ASSURE CORROSION REMOVAL. TREATED SPOT FACE AREA BY ETCHING, AND FLAPPER PEENING. ACCOMPLISHED REPAIR PER EA 018544.