UPDATE: CNN reports that BP has resumed its "top kill" efforts to plug the oil well.
COVINGTON, La. – BP's efforts to plug its gushing oil well suffered a setback late Wednesday. The New York Times reported that the company made the decision to stop its "top kill" plug attempt because too much of the heavy, man-made mud being used to plug the well was escaping from the leak, along with a mixture of oil.
According to the Times, a BP technician said that engineers will revise their plans and hope to resume "top kill" efforts by midnight.
"Top kill" is the company's boldest attempt yet to plug the gusher that has spewed millions of gallons of oil over the last five weeks. BP hopes that by pumping mud into the well, it can overpower the steady stream of oil. The company wants to eventually inject cement into the well to permanently seal it.
The stakes are high. Fisherman, hotel and restaurant owners, politicians and residents along the coast are fed up with BP's so far ineffective attempts to stop the oil leak that sprang after an offshore drilling rig exploded April 20. Eleven workers were killed, and by the most conservative estimate, 7 million gallons of crude have spilled into the Gulf, fouling Louisiana's marshes and coating birds and other wildlife.
The top kill has worked above ground but has never before been tried 5,000 feet beneath the sea. Company officials peg its chance of success at 60 to 70 percent.
President Barack Obama said "there's no guarantees" it will work. The president planned a trip to Louisiana on Friday.
"We're going to bring every resource necessary to put a stop to this thing," he said.
Meanwhile, dozens of witness statements obtained by The Associated Press show a combination of equipment failure and a deference to the chain of command impeded the system that should have stopped the gusher before it became an environmental disaster.
In a handwritten statement to the Coast Guard obtained by the AP, Transocean rig worker Truitt Crawford said: "I overheard upper management talking saying that BP was taking shortcuts by displacing the well with saltwater instead of mud without sealing the well with cement plugs, this is why it blew out."
At a Coast Guard hearing in New Orleans, Doug Brown, chief rig mechanic aboard the platform, testified that the trouble began at a meeting hours before the blowout, with a "skirmish" between a BP official and rig workers who did not want to replace heavy drilling fluid in the well with saltwater.
The switch presumably would have allowed the company to remove the fluid and use it for another project, but the seawater would have provided less weight to counteract the surging pressure from the ocean depths.
Brown said the BP official, whom he identified only as the "company man," overruled the drillers, declaring, "This is how it's going to be." Brown said the top Transocean official on the rig grumbled, "Well, I guess that's what we have those pinchers for," which he took to be a reference to devices on the blowout preventer, the five-story piece of equipment that can slam a well shut in an emergency.
A live video stream Wednesday showed pictures of the blowout preventer, as well as the oil gushing out. At other times, the feed showed mud spewing out, but BP said this was not cause for alarm.
A weak spot in the blowout preventer could blow under the pressure, causing a brand new leak.
Gene Beck, a petroleum engineering professor at Texas A&M in College Station, said the endeavor would likely fail quickly if the mud could not overcome the pressure of the oil.
"The longer it goes, maybe the better news that is," Beck said.
Frustration with BP and the federal government has only grown since then as efforts to stop the leak have failed.
Louisiana Gov. Bobby Jindal and Plaquemines Parish President Billy Nungesser, both outspoken critics, led a boat tour around the oil-fouled delta near the mouth of the Mississippi River.
Through the Mississippi's South Pass, there were miles-long passages that showed no indication of the oil, and the air smelled fresh and salty. Nearby fish were leaping and tiny seabirds dove into the water.
But not far away at Pass a Loutre, the odor wafting above the oily water was that of an auto shop.
"We have yet to see a plan from the Coast Guard, a plan from BP, a plan to keep it from coming in, a plan to pick it up," Nungesser said of the oil.
"There's no wildlife in Pass a Loutre. It's all dead," Nungesser said.
Associated Press writers Mike Kunzelman and Kevin McGill in New Orleans, Jeff Donn in Boston, Julie Pace in Fremont, Calif., Ben Nuckols in Covington contributed to this story.