RedactedNarrative: Unit 1 was heading north in the Cooper River with individual as the operator.  He noticed his GPS unit was not functioning correctly along with other  electronic problems.  He told operator to grab the wheel so he could check on the batteries and they switch.  While turning into Bull Creek from Cooper River, Unit 1 made contact with an oyster bank and ejected everyone from the vessel.  Unit 1 then went across Bull Creek and ran roughly 50 yards up into the marsh grass.  Unit 1 motor ran for roughly 2 hours, grounded in the marsh, before it shut off.  All occupants of unit 1 were rescued by Coast Guard and taken to Alljoy Boat Landing for medical care.  Two victims were transported to the hospital. One victim transported was a juvenile and information will be attached to supp. report.