The Deepwater Horizon oil rig burned on April 21, 2010. U.S. Coast Guard/Getty Images hide caption
Gulf Oil Spill: Containment And Clean Up
The Deepwater Horizon oil rig burned on April 21, 2010. U.S. Coast Guard/Getty Images hide caption
April 21, 2010: Fire boats battle the blaze on the Deepwater Horizon rig. U.S. Coast Guard/Getty Images hide caption
Oobleck has some novel physical properties. When it's moved slowly, it acts smooth and runny, like a liquid. But move it quickly and forcefully, and it locks up, becoming almost solid. Jonathan Makiri/NPR hide caption
As the Deepwater Horizon oil rig burned last April, millions of barrels of oil were beginning to make their way out of the blown-out well underneath. U.S. Coast Guard/Getty Images hide caption
This image, from a video feed from a remote submarine, shows BP's Macondo well leaking natural gas on May 12, 2010. A new study concludes that the vast quantity of methane gas that spewed from the well in the Gulf of Mexico was rapidly eaten by bacteria. BP PLC/AP hide caption
The Deepwater Horizon oil rig burns in the Gulf of Mexico last April. An excerpt of a presidential commission's probe into the rig explosion says risky decisions contributed to the disaster. Gerald Herbert/AP hide caption
Attorney General Eric Holder announces a civil lawsuit against BP and eight others in an effort to recover billions of dollars from the Gulf oil spill. At right is Environmental Protection Agency Administrator Lisa Jackson. Alex Wong/Getty Images hide caption
Oysterman Mitch Jurisich steers a small boat around his family's oyster beds off the coast of Empire, La. He hasn't harvested many oysters since oil from the BP spill drifted into the area in June. Tamara Keith/NPR hide caption
Fred Bartlit Jr., chief investigator of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling, at the public hearing in Washington, D.C., on Monday. J. Scott Applewhite/AP hide caption
Boats battle a fire at the Deepwater Horizon oil rig in April. Eleven people were killed in the blast. U.S. Coast Guard/Getty Images hide caption
Waves breaking on the shore in Orange Beach, Ala., leave behind an oily residue. Mayor Tony Kennon expects BP to restore the town's beaches to sugar white condition. Debbie Elliott/NPR hide caption
The sun sets over an oil platform waiting to be towed out into the Gulf of Mexico at Port Fourchon in Louisiana. Getty Images hide caption