Investigation into tugboat grounding on Bligh Reef begins


As the drama around the tugboat grounding in Prince William Sound draws to a close, big questions still linger about what happened.

The two biggest: Why did the 136-foot Pathfinder tug go aground at Bligh Reef, one of the most famous shipping hazards in the world? And, how much of the thousands of gallons of diesel fuel it carried leaked when the reef ripped open the boat's hull?