A double layer of oil booms are set up around one of the Chandeleur Islands, Louisiana May 7, 2010 as seen from a plane used by the environmental group Mobile Baykeeper and Southwings to look at the damage caused by the oil spill. Oil workers, volunteers and the military have been battling to shut off a gushing oil leak in the Gulf of Mexico and stop the huge spreading slick from reaching major ports, tourist beaches, wildlife refuges and fishing grounds. REUTERS/Brian Snyder (UNITED STATES - Tags: DISASTER ENERGY ENVIRONMENT)