The report and BP's so-far successful "static kill" operations bolster a top U.S. energy official's statement Wednesday that the months-long spill crisis is "turning a corner."
"We definitely are making progress. The oil hasn't been leaking for some time," Carol Browner, director of the White House Office of Energy and Climate Change Policy, said on cnn.
"The static kill is going well, but ultimately, it's the relief wells we ordered drilled that will be the 'final kill-kill.' Probably, in the next 10 to 14 days that will be done, but (it was) an important step last night," Browner said.
White House spokesman Robert Gibbs on Wednesday hailed the " beginning of the end" of efforts to stop the leak and contain the oil in the Gulf of Mexico.
"It is sort of the beginning of the end of the sealing and containment phase of this operation," Gibbs told reporters.
However, he also said: "There's a lot of reasons why there's no ' Mission Accomplished' banner."
"There's a lot of work to do," he said. "We're not leaving the area, and more importantly, we're not leaving behind any commitment to clean up the damage that's been done and repair and restore the Gulf."