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

itoggle caption J. Scott Applewhite/AP

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

itoggle caption U.S. Coast Guard/Getty Images

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

itoggle caption Debbie Elliott/NPR

Retired Coast Guard Adm. Thad Allen testifies Monday before the commission investigating the Gulf of Mexico oil spill. Though Allen was the government's leader of the spill response, he acknowledged it was not always clear to the public who was in charge. Mark Wilson/Getty Images hide caption

itoggle caption Mark Wilson/Getty Images

Bayou Bienvenue in New Orleans is an example of south Louisiana’s wetland loss. Fifty years ago, this was a productive freshwater marsh with cypress and tupelo trees. Today, stumps are all that remain, as saltwater has encroached inland. Debbie Elliot/NPR hide caption

itoggle caption Debbie Elliot/NPR