  FE345SS/90--OPR-B660-HE; UNIDENTIFIED OBSTRUCTION SHOWN ON SONARGRAMS OBTAINED DURING THE INVESTIGATION OF AWOIS 1858 (36 FT, WRECK, LAZY DAYS). ESTIMATED DEPTH ON CONTACT IS 11.6M (MLLW) AS DETERMINED FROM SIDE SCAN RECORDS. POSITION COMPUTED USING OF