Fire boat response crews battle the blazing remnants of BP's Deepwater Horizon oil rig at the site of the gulf oil spill off Louisiana in this April 21, 2010 handout file photo. When BP's Deepwater Horizon oil rig exploded and sank in the Gulf of Mexico last April, killing 11 workers, authorities first reported that no crude was leaking into the ocean. They were wrong. One year on, oil from the largest spill in U.S. history clogs wetlands, pollutes the ocean and endangers wildlife, not to mention the toll it has inflicted on the coastal economies of Florida, Mississippi, Alabama and especially Louisiana. REUTERS/U.S. Coast Guard/Handout/Files (UNITED STATES - Tags: ANNIVERSARY BUSINESS DISASTER ENERGY ENVIRONMENT) FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS