  LNM42/99(10/19/99)--17th CGD;  DANGEROUS UNDERWATER ROCK 1¼ FM, PA, ADDED.  THE P/V GLACIAL EXPLORER RAN AGROUND JUNE 13, 1998 ON A SUBMERGED ROCK AT POSITION 59-55.453 N, 149-42.991 W (NAD83) (POSITION SOURCE MOST LIKELY GPS WITHOUT DIFFERENTIAL CORRE