A sense of doom settled over the American coastline from Louisiana to Florida on Saturday as a massive oil slick spewing from a ruptured well kept growing, and experts warned that an uncontrolled gusher could create a nightmare scenario if the Gulf Stream carries it toward the Atlantic.
President Barack Obama planned to visit the region Sunday to assess the situation amid growing criticism that the government and oil company BP PLC should have done more to stave off the disaster. Meanwhile, efforts to stem the flow and remove oil from the surface by skimming it, burning it or spiking it with chemicals to disperse it continued with little success.
"These people, we've been beaten down, disaster after disaster," said Matt O'Brien of Venice, whose fledgling wholesale shrimp dock business is under threat from the spill.
"They've all got a long stare in their eye," he said. "They come asking me what I think's going to happen. I ain't got no answers for them. I ain't got no answers for my investors. I ain't got no answers."
He wasn't alone. As the spill surged toward disastrous proportions, critical questions lingered: Who created the conditions that caused the gusher? Did BP and the government react robustly enough in its early days? And, most important, how can it be stopped before the damage gets worse?
The Coast Guard conceded Saturday that it's nearly impossible to know how much oil has gushed since the April 20 rig explosion, after saying earlier it was at least 1.6 million gallons — equivalent to about 2 1/2 Olympic-sized swimming pools. The blast killed 11 workers and threatened beaches, fragile marshes and marine mammals, along with fishing grounds that are among the world's most productive.
Even at that rate, the spill should eclipse the 1989 Exxon Valdez incident as the worst U.S. oil disaster in history within about a week. But a growing number of experts warned that the situation may already be much worse.
The oil slick over the water's surface appeared to triple in size over the past two days, which could indicate an increase in the rate that oil is spewing from the well, according to one analysis of images collected from satellites and reviewed by the University of Miami. While it's hard to judge the volume of oil by satellite because of depth, it does show an indication of change in growth, experts said.
"The spill and the spreading is getting so much faster and expanding much quicker than they estimated," said Hans Graber, executive director of the university's Center for Southeastern Tropical Advanced Remote Sensing. "Clearly, in the last couple of days, there was a big change in the size."
Florida State University oceanography professor Ian R. MacDonald said his examination of Coast Guard charts and satellite images indicated that 8 million to 9 million gallons had already spilled by April 28.
Doug Suttles, BP's chief operating officer for exploration and production, said it was impossible to know just how much oil was gushing from the well, but said the company and federal officials were preparing for the worst-case scenario.
Oil industry experts and officials are reluctant to describe what, exactly, a worst-case scenario would look like — but if the oil gets into the Gulf Stream and carries it to the beaches of Florida, it stands to be an environmental and economic disaster of epic proportions.
The Deepwater Horizon well is at the end of one branch of the Gulf Stream, the famed warm-water current that flows from the Gulf of Mexico to the North Atlantic. Several experts said that if the oil enters the stream, it would flow around the southern tip of Florida and up the eastern seaboard.
"It will be on the East Coast of Florida in almost no time," Graber said. "I don't think we can prevent that. It's more of a question of when rather than if."
At the joint command center run by the government and BP near New Orleans, a Coast Guard spokesman maintained Saturday that the leakage remained around 5,000 barrels, or 200,000 gallons, per day.
But Coast Guard Adm. Thad Allen, appointed Saturday by Obama to lead the government's oil spill response, said no one could pinpoint how much oil is leaking from the ruptured well because it is about a mile underwater.
"And, in fact, any exact estimation of what's flowing out of those pipes down there is probably impossible at this time due to the depth of the water and our ability to try and assess that from remotely operated vehicles and video," Allen said during a conference call.
From land, the scope of the crisis was difficult to see. As of Saturday afternoon, only a light sheen of oil had washed ashore in some places.
The real threat lurked offshore in a swelling, churning slick of dense, rust-colored oil the size of Puerto Rico. From the endless salt marshes of Louisiana to the white-sand beaches of Florida, there is uncertainty and frustration over how the crisis got to this point and what will unfold in the coming days, weeks and months.
The concerns are both environmental and economic. The fishing industry is worried that marine life will die — and that no one will want to buy products from contaminated water anyway. Tourism officials are worried that vacationers won't want to visit oil-tainted beaches. And environmentalists are worried about how the oil will affect the countless birds, coral and mammals in and near the Gulf.
"We are just waiting," said Meghan Calhoun, a spokeswoman from the Audubon Aquarium of the Americas in New Orleans. "We know they are out there. Unfortunately the weather has been too bad for the Coast Guard and NOAA to get out there and look for animals for us."
Fishermen and boaters want to help contain the oil. But on Saturday, they were again hampered by high winds and rough waves that splashed over the miles of orange and yellow inflatable booms strung along the coast, rendering them largely ineffective. Some coastal Louisiana residents complained that BP, which owns the rig, was hampering mitigation efforts.
"They're letting an oil company tell a state what to do," said 57-year-old Raymond Schmitt, in Venice preparing his boat to take a French television crew on a tour.
"I don't know what they are waiting on," Schmitt said. He didn't think conditions were dangerous. "No, I'm not happy with the protection, but I'm sure the oil company is saving money."
As bad as the oil spill looks on the surface, it may be only half the problem, said University of California Berkeley engineering professor Robert Bea, who serves on a National Academy of Engineering panel on oil pipeline safety.
"There's an equal amount that could be subsurface too," said Bea, who worked for Shell Oil Co. in the 1960s when the last big northern Gulf of Mexico oil well blowout occurred. And that oil below the surface "is damn near impossible to track."
Louisiana State University professor Ed Overton, who heads a federal chemical hazard assessment team for oil spills, worries about a total collapse of the pipe inserted into the well. If that happens, there would be no warning and the resulting gusher could be even more devastating because regulating flow would then be impossible.
"When these things go, they go KABOOM," he said. "If this thing does collapse, we've got a big, big blow."
BP has not said how much oil is beneath the Gulf seabed Deepwater Horizon was tapping, but a company official speaking on condition of anonymity because he was not authorized to discuss the volume of reserves, confirmed reports that it was tens of millions of barrels.
At a church in the Lower 9th Ward of New Orleans, EPA Administrator Lisa Jackson told a gathering of community leaders that the spill has created an "environmental challenge of the highest order."
"Every oil spill is a challenge. But this is quite different because of where it is, because the marshes are so different than the beach and the coastline in Alaska when we had the Valdez," she said. "This one is complicated by the fact that the well head is 5,000 feet below the water."
The Coast Guard's Allen said Saturday that a test of new technology used to reduce the amount of oil rising to the surface seemed to be successful.
During the test Friday, an underwater robot shot a chemical meant to break down the oil at the site of the leak rather than spraying it on the surface from boats or planes, where the compound can miss the oil slick.
In Pass Christian, Miss., 61-year-old Jimmy Rowell, a third-generation shrimp and oyster fisherman, worked on his boat at the harbor and stared out at the choppy waters.
"It's over for us. If this oil comes ashore, it's just over for us," Rowell said angrily, rubbing his forehead. "Nobody wants no oily shrimp."
Associated Press writers Tamara Lush, Brian Skoloff, Melissa Nelson, Mary Foster, Michael Kunzelman, Chris Kahn, Vicki Smith, Janet McConnaughey, Alan Sayre and AP Photographer Dave Martin contributed.
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