CRESCENT CITY, Calif. -- The Derrick Barge-24, a heavy-lift crane barge that will be used to facilitate the removal of pollution threats within the inner boat basin, enters the Crescent City Inner Boat Basin, Thursday, March 24, 2011. The Unified Command's primary operational goal is to mitigate environmental impact to the harbor, so Crescent City can begin restoring its harbor as soon as possible. U.S. Coast Guard photo by Petty Officer 3rd Class Levi Read.