FILE - Greenpeace worker Lindsey Allen collects samples of oil that washed up along the mouth of the Mississippi River near Venice, La., in this file photo taken May 19, 2010, a month a

 

              FILE - Greenpeace worker Lindsey Allen collects samples of oil that washed up along the mouth of the Mississippi River near Venice, La., in this file photo taken May 19, 2010, a month a
FILE - Greenpeace worker Lindsey Allen collects samples of oil that washed up along the mouth of the Mississippi River near Venice, La., in this file photo taken May 19, 2010, a month after the Deepwater Horizon oil rig explosion in the Gulf of Mexico. A high-stakes trial to assign blame and help figure out exactly how much more BP and other companies should pay for the spill began Monday, Feb. 25, 2013. (AP Photo/Charlie Riedel, File)