Anger was mounting as heavy oil blackened Louisiana's marshes and beaches and efforts to cap the oil which has been gushing into the Gulf of Mexico for more than a month met with more delays.
Initially scheduled to begin on Sunday, BP's latest attempt to cap a leak in a ruptured pipe 5,000 feet (1,500 meters) below the surface is not expected to get underway until Tuesday at the earliest.
Crews used submarine robots Saturday to position equipment for the "top kill" attempt to plug the leak with heavy mud and then seal it with cement.
"There's a lot of staging that must go on -- on the surface of the water as well as on the seafloor -- testing, getting the mud and the ship staged," BP spokesman John Curry told AFP.
But while a fleet of skimmers did its best to contain the massive slick which has spread across the gulf and begun to make its way towards Florida, oil washed past protective booms and continued to sully miles of Louisiana's coastline.
Susan Villiers, 52, stared with frustration at the empty waters as she walked along the oil-soaked beach of Grand Isle, Louisiana.
"Everybody is angry because they want to see action," said Villers, who has three fishing boats sitting idle because of the spill.
"They want to see boats deploying booms and nothing's happening."
With the federal government facing accusations of lax supervision of lucrative offshore oil drilling, President Barack Obama vowed to hold Washington accountable and warned that the future of the industry hinges on assurances such a disaster "never happens again."
Obama hinted for the first time that a criminal investigation could be launched as he unveiled a presidential commission aimed at probing the "root causes" of the spill.
He noted concerns about the "cozy relationship between oil and gas companies and agencies that regulate them" and said the "disaster was a breakdown of responsibility on the part of BP and perhaps others, including Transocean and Halliburton."
Obama gave the bipartisan presidential commission six months to report its findings and provide recommendations on how the oil industry can prevent and mitigate the impact of any future spills.
"If the laws on our books are inadequate to prevent such an oil spill, or if we didn't enforce those laws -- I want to know it," Obama said in his weekly radio address Saturday.
"I want to know what worked and what didn't work in our response to the disaster, and where oversight of the oil and gas industry broke down."
Some 1,100 vessels, over 24,900 personnel and more than two million feet of protective boom have been deployed so far by BP and federal, state and local agencies.
They have recovered over 9.7 million gallons of oily water so far. BP says it has already spent over 700 million dollars on the cleanup.
But for parts of the Gulf Coast's fragile ecosystem, it was all too little, too late.
A viscous blackish-orange slick sloshed ashore Grand Isle, Louisiana, forcing officials to close its popular tourist beach.
Volunteers armed with spades were locked in a desperate battle to scoop up the oil into plastic bags.
"It was dirty at 6:00 am. We cleaned it up. When we came back from lunch it just looked exactly the same," said Eric Thomson, 19, wearing a white safety helmet, black boots and dark glasses under the hot sun.
Even at the lowest estimates, more than six million gallons of crude have soiled Gulf waters since the BP-operated Deepwater Horizon rig sank spectacularly some 52 miles offshore on April 22, two days after an explosion that claimed 11 workers' lives.
Just how much oil is gushing from the rig's wreckage has been a major point of contention, with BP initially putting the figure at 5,000 barrels, or 210,000 gallons, a day.
Independent experts examining video of the ruptured pipe have estimated that the flow from the two leaks could be as high as 120,000 barrels per day.
BP is currently suctioning up an average of about 2,100 barrels of oil a day with a mile-long tube inserted into the ruptured pipe.
It will take at least two months for relief wells to be completed and hopes of stopping the flow are currently pinned on a "top kill" operation.
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