WASHINGTON (Reuters) - The Obama administration was over-optimistic about BP’s ability to handle the oil spill after the company’s Gulf well exploded in April and blocked government spill estimates that might have prompted quicker action, an investigative panel said on Wednesday.

Smoke billows from a controlled burn of spilled oil off the Louisiana coast in the Gulf of Mexico, June 13, 2010. REUTERS/Sean Gardner

The revelations from the National Oil Spill Commission, whose members were appointed by President Barack Obama, could be embarrassing as Obama’s Democratic Party struggles to retain control of the U.S. Congress in the elections on November 2.

The commission said that after the rig in the Gulf of Mexico exploded on April 20, killing 11 workers, the government was too optimistic about the British oil company’s ability to bring the ruptured well under control.

“For the first ten days of the spill, it appears that a sense of over-optimism affected responders. Responders almost uniformly noted that, while they understood that they were facing a major spill, they believed that BP would get the well under control,” the commission wrote.

It said: “Though some of the command structure was put in place very quickly, in other respects the mobilization of resources to combat the spill seemed to lag.”

Large sections of the Gulf of Mexico were closed to fishing, hundreds of miles of shoreline were polluted and the coastal economy, including tourism and fisheries, was disrupted before the well was capped on July 15 after the worst offshore oil leak in U.S. history.

BLOCKED DATA

The commission also criticized the White House for blocking early worst case estimates of the oil spill, which it said may have affected how fast resources were assembled to fight it.

The panel said the National Oceanic and Atmospheric Administration (NOAA) wanted to release some of its worst-case spill models on the accident in late April or early May. But the White House Office of Management and Budget (OMB) blocked the move to make the information public.

The White House decision to block the estimates came as BP was being criticized for failing to provide accurate information on the amount of oil that was leaking.

In a joint statement, the directors of OMB and NOAA did not deny that NOAA’s early spill estimate was blocked. Instead, they said NOAA’s early analysis was incomplete because it did not take into account the measures to control the oil, like using floating booms, skimming the oil and burning it at sea.

However, those measures would not have stopped the oil from spewing out of BP’s broken well.

The agency heads noted that other senior government officials told the public in early May what the worst-case flow rate could be.

DID THE OIL DISAPPEAR?

Commission staff said it established that the possibility of releasing the worst-case discharge figures was at least discussed at the government’s Unified Command level that oversaw efforts to plug the well and clean up the oil.

The panel said in the end government teams and independent scientists came up with the same approximate figure on the total amount of oil that spilled from the well -- roughly 5 million barrels of oil leaked, with 4.2 million barrels pouring into Gulf waters and the rest being recovered.

However, commission staff questioned comments made by Carol Browner, the White House’s energy and climate change director, after the well was plugged that “more than three-quarters of the oil is gone.”

The panel said about 40 percent of the oil that spilled and was labeled as “dissolved” and “dispersed” was potentially being biodegraded, but was not “gone.”

“Dispersed or dissolved oil may still be present in the water, and even evaporated oil remains in the atmosphere for a short time,” the commission said.

The panel also said the government went overboard in placing boom to stop the oil, especially in Louisiana, where directions went out to “keep the parishes happy.”

As a result boom was placed everywhere, including in passes where fast tidal currents made it ineffective, and in places where it was unlikely to encounter any oil. Boom was also put in environmentally sensitive areas such as marshes, where severe storms blew it onto delicate grasses and habitat.

“The boom wars never reached a resolution. In many instances, responders knew that in deploying boom they were responding to the politics of the spill rather than the spill itself,” the commission said.