  SOURCE UNKNOWN--  PILE ON 12204 AND A SUBM GROIN OR RIER RUINS ON 12205.  FEATURE FIRST APPEARS ON THE 21ST EDITION OF 12204 IN 1976.  CL1872/71 HAS THE FEATURE AS PIER RUINS WHICH WERE CLEARLY VISIBLE (CHART 12205).  THE AWOIS POSITION IS THE OFFSHORE