As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX: RT UPPER WING FUEL TANK ACCESS HOLE REBATES FROM STA YW 42.00 TO YW191.20 HAVE FRETTING CORROSION AROUND BOLT HOLES, KNIFE MARKS ON THE UPPER SURFACE. MAINTENANCE REPAIRED IAW RD 8/4-57-665, HORIZON EA 6-57-486 AND NDTM PART 1, 51-00-04 AND 51-00-06.