The U.S. Coast Guard said it is monitoring a barge with heavy fuel oil aground after a two towboats collided near Plaquemine, La., at mile marker 43.5 on the Port Allen route of the Gulf intracoastal waterway.Coast Guard Marine Safety Unit Baton Rouge responded after watchstanders at Coast Guard Sector New Orleans were notified that the vessels Creole Crusader and the Jack Odom collided at