KENNER, La. — As BP continued a hydraulic arm-wrestle with its renegade well, President Barack Obama toured Louisiana's soiled beaches Friday and vowed to take responsibility for solving the oil spill crisis.
"I am the president and the buck stops with me," he said during a beachfront gathering of Gulf Coast governors — including Florida's Charlie Crist — senators and local officials in Grand Isle.
He said the government would hold BP legally and financially responsible for the damage.
But as demands mount for a more vigorous federal response to the oil seeping into wetlands, curtailing the region's fishing economy and drying up tourism, Obama also sought to lower expectations.
"America has never experienced an event like this before," he said. "This means that, as we respond to it, not every judgment we make is going to be right the first time out."
Given the magnitude of what he called "a man-made catastrophe that is still evolving," Obama added, "There are not going to be silver bullets or a lot of perfect answers for some of the challenges that we face."
Obama's visit, on a humid, nearly windless day, was his second to the gulf since the April 20 explosion that killed 11 rig workers and triggered the biggest oil spill in U.S. history. As much as 29 million gallons may have spilled so far, according to government estimates.
On his way to a briefing in the town of Grand Isle, the president stopped at Fourchon Beach, where he inspected booms, picked up a handful of tar balls and pointed out dolphins swimming offshore as evidence of the gulf's "precious wildlife."
On Grand Isle's Main Street, signs read, "Lead, follow or get out of the Gulf," "Welcome Mr. President" and "Shame on you BP." Obama's arrival brought people out of their beach houses to perch on porch swings and lawn chairs.
'Junk shot' added to 'top kill' efforts
Nearly 50 miles offshore, BP struggled to overwhelm the geyser of oil pushing up its well by pumping heavy drilling fluid and other "junk" materials into the well at high speed and under high pressure. BP officials said they had made progress but would be unable to judge the ultimate success of the operation before Sunday.
Chief operating officer Doug Suttles called the "top kill" operation "a bit like a roller-coaster," alternating between shooting in drilling mud, pausing to take pressure tests, and pushing in rubber and other materials. "The fact that it stopped and started is not unusual," he added.
Should the top kill fail, Suttles said, engineers are preparing a "lower marine riser package" to place over the blowout preventer and are considering stacking another blowout preventer above that apparatus. Drilling of one relief well halted, while another continued.
Obama announced that the federal government would triple the number of personnel involved in the cleanup and monitoring of the spill in places where oil has hit the shore or is within 24 hours of impact.
So far, 20,000 people have been mobilized overall, including 1,400 National Guard soldiers.
Doctors and scientists are being deployed along the coast, at BP's expense, to monitor residents and track the health effects of the spill and offer care, Obama said.
Researchers find more evidence of plumes
A day after scientists from the University of South Florida reported finding a huge plume of oil extending miles east of the leaking BP well, a Louisiana scientist on Friday said his crew had located another vast plume of oily globs, miles in the opposite direction.
James H. Cowan Jr., a professor at Louisiana State University, said his crew on Wednesday found a plume of oil in a section of the gulf 75 miles northwest of the source of the leak.
Cowan said that his crew sent a remotely controlled submarine into the water and found it full of oily globules, from the size of a thumbnail to the size of a golf ball. Unlike the plume found east of the leak — in which the oil was so dissolved the contaminated water appeared clear — Cowan said the oil at this site was so thick that the sub returned to the surface entirely black.
Cowan said that the submarine traveled about 400 feet down, close to the sea floor, and found oil all the way down. "We really never found either end of it," he said. He said he did not know how wide the plume actually was, or how far it stretched away to the west.
Meanwhile, some of the scientists who had disclosed evidence of undersea oil plumes about two weeks ago — a claim had been greeted skeptically by the government — found more evidence for the existence of the plumes. Samantha Joye of the University of Georgia and Vernon Asper of the University of Southern Mississippi, were aboard the Walton Smith west of the oil leak as water samples were pulled up that contained highly diffuse oil not visible to the naked eye. When several gallons of the water were forced through a fine filter, tiny black oil droplets appeared.
Even in that diffuse form, the plumes were having a drastic impact on the chemistry of the ocean, with dissolved oxygen levels plunging as each plume drifted through the sea.
That, Joye said, was most likely because bacteria were ramping up to consume the oil and gas — a good thing, overall, but it was creating a heavy demand for oxygen and other nutrients. Aside from the toxic effect of the oil, the declining oxygen was a potential threat to sea life.
The National Oceanic and Atmospheric Administration has extended the closed fishing area in the Gulf of Mexico to an area that represents 60,683 square miles, which is about 25 percent of federal waters in the gulf.
Criminal investigation of BP is under way
In Washington, Interior Secretary Ken Salazar named Bureau of Land Management director Bob Abbey acting director of the Minerals Management Service. Elizabeth Birnbaum, the Obama administration's director of 11 months, resigned this week amid unrelenting criticism of the federal government's lax oversight of BP and the rest of the offshore oil industry.
Also in Washington, a team of top federal prosecutors and investigators has taken the first steps toward a formal criminal investigation into BP's actions before and after the oil rig disaster.
The investigators are focusing on whether BP skirted federal safety regulations and misled the U.S. government by claiming it could quickly clean up an environmental accident.
Information from the Washington Post, Miami Herald and New York Times was used in this report.