WASHINGTON — As BP neared a fix that's expected to kill the runaway well in the Gulf of Mexico, the government Monday said that 10 to 12 times more oil had been flowing from the well than it originally thought.
New estimates released Monday by a government-led team of scientists found that as much as 62,000 barrels of oil were leaking from the well each day at its peak — far beyond the initial estimate of 5,000 barrels a day and more in line with what scientists told McClatchy it was.
The new estimates raise questions about whether the early response ever anticipated the disaster's size and scope. The well gushed an estimated 4.9 million barrels for nearly three months before BP put in place a temporary cap 18 days ago.
The government now estimates that 53,000 barrels were leaking each day before BP installed the cap. Only 800,000 barrels — about 16 percent of the total — was captured before flowing into the ocean.
Now, BP is finalizing plans to begin a "static kill," a process that would force down any remaining oil and gas in the well by pumping heavy drilling mud into it.
"We'll just be slowly pumping the mud in initially and it will gradually build up pressure," BP's Kent Wells said Monday during a technical briefing. "We'll be carefully monitoring the pressures and the volumes. The team will be looking and making sure we do everything to get this well killed, if at all possible."
That procedure is expected to begin today and could stretch into Wednesday. If it works — and the White House said it is "watching cautiously" — BP will move quickly this week to begin cementing the well closed permanently.
The company still must decide how best to cement the well closed: from the top or through one of the relief wells currently being drilled.
There's still some uncertainty about the conditions deep inside the well, and until they pump mud into it, company officials won't know the safest way to proceed, said Thad Allen, the top federal official in charge of the spill response.
"We don't know the condition of the well until we start to put mud in it," Allen said.
Meanwhile, Allen and the Environmental Protection Agency on Monday defended the safety of chemicals credited with breaking up the oil into tiny droplets and dispersing it into the Gulf.
The EPA said Monday that those dispersants hastened the decomposition of the oil, a process that may also have kept vast quantities of oil from fouling the shoreline. BP, which used more than 1.84 million gallons of dispersants, stopped applying them shortly after it put the cap in place.
The EPA said Monday that its new study found the dispersants used to break up oil in the Gulf are no more toxic when mixed with oil than the oil is on its own.
So far, the government's monitoring data shows no accumulation of dispersant in marine life that was tested, including on juvenile shrimp and small fish that are found in the Gulf and are commonly used in toxicity testing.