The 93 foot long, 134 dwt tug Justice went aground in Buzzards Bay, Cape Code, Massachusetts.  The tug sustained damage to its starboard drive and lost its propeller.  No reports of injuries.  Some 600 gallons of gear oil leaked into the water leaving a visible oil sheen.  The tug owners dispatched an environmental cleanup crew to the scene.  The Coast Guard has launched an investigation into the incident.