Earlier this week, BP CEO Tony Hayward said the spill was "relatively tiny" and the environmental effects would be minimal. But thick oil has already and some has .
"We don't know whether it's going to be minimal or not. It could be catastrophic," Salazar told CBS' "The Early Show" Thursday. "BP is on the hook to make sure that everything is made whole including the environment and the people that will be affected."
Special Section: Disaster in the Gulf
Since the Deepwater Horizon oil rig exploded and sank April 20, BP has estimated 5,000 barrels of oil were flowing from the underwater well into the Gulf. Independent scientists, however, have said that the crude is flowing at a much higher rate - 95,000 barrels a day.
"The government will be making its own independent verification of what the total numbers are," Salazar said. "The American people are entitled to know exactly how much has spilled out in to the Gulf and BP is responsible to make sure that whatever damages that occur are in fact made. So getting this number and being accurate is imperative."
The much higher independent estimates have come out after BP released live video of the gusher.
Steve Wereley, a mechanical engineer at Purdue University in Indiana, told The Associated Press that he is sticking with his estimate that 3.9 million gallons a day is spewing from two leaks.
"I don't see any scenario where (BP's) numbers would be accurate," he said at a congressional hearing Wednesday.
His estimate of the amount leaked to date, which he calls conservative and says has a margin of error of plus or minus 20 percent, is 126 million gallons - or more than 11 times the total leaked from the Exxon Valdez disaster in 1989. The official estimate is closer to 6 million gallons.
Salazar said the 5,000 barrel-a-day figures were the "best estimates at the time" and will be adjusted as more analysis is done.
Rep. Edward Markey, D-Mass., called on BP to release live video feeds of the the oil so independent scientists can more accurately calculate the flow rate. He questioned why such data isn't readily being made public.
BP has received thousands of ideas from the public on how to stop the oil gusher, but some inventors are complaining that their efforts are being ignored.
Oil-eating bacteria, bombs and a device that resembles a giant shower curtain are among the 10,000 fixes people have proposed to counter the growing environmental threat. BP is taking a closer look at 700 of the ideas, but the oil company has yet to use any of them.
"They're clearly out of ideas, and there's a whole world of people willing to do this free of charge," said Dwayne Spradlin, CEO of InnoCentive Inc., which has created an online network of experts to solve problems.
BP spokesman Mark Salt said the company wants the public's help, but that considering proposed fixes takes time.
"They're taking bits of ideas from lots of places," Salt said. "This is not just a PR stunt."
BP succeeded in partially siphoning away the leak over the weekend, when it hooked up a mile-long tube to the broken pipe, sending some of the oil to a ship on the surface. And the company said Wednesday it hopes to begin shooting a mixture known as drilling mud into the blown-out well by Sunday.
The "top kill" method involves directing heavy mud into crippled equipment on top of the well, then aiming cement at it to permanently keep down the oil. Even if it works, it could take several weeks to complete.
If it fails, BP is considering a "junk shot," which involves shooting knotted rope, pieces of tires and golf balls into the blowout preventer. Crews hope they will lodge into the nooks and crannies of the device to plug it.
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