ZCZC FA59 302140 UTC SEP ESTONIAN NAV WARN 166/26 GULF OF FINLAND 1 TO 3 OCT UNDERWATER SURVEY BY VESSEL EVA-316 W OF VAINDLOO ISLAND 59-51.8N 025-52.7E 59-51.6N 025-58.1E 59-51.8N 026-00.2E 59-50.1N 026-00.4E 59-50.1N 026-07.0E 59-49.0N 026-05.4E 59-49.0N 026-00.1E 59-50.0N 025-57.0E 59-46.5N 025-56.9E 59-46.7N 025-44.9E 59-50.1N 025-46.2E 59-50.1N 025-52.7E KEEP DISTANCE 2 NM FROM WORKING VESSEL NNNN