The oil spill in the Gulf of Mexico is probably “the biggest environmental disaster” that the United States has ever experienced, senior White House official Carol Browner said Sunday. Browner, a White House adviser on energy and climate change, told NBC's “Meet the Press” that the leak was “probably the biggest environmental disaster we've ever faced in this country.” Estimates now suggest that between 12,000 to 19,000 barrels of crude are gushing into the Gulf each day from a well pipe damaged when the Deepwater Horizon oil rig exploded and then sank two days later on April 22. That means “more oil is leaking in the Gulf of Mexico than at any other time in our history. It means there is more oil than the Exxon Valdez,” Browner said. Approximately 11 million gallons of crude spilled into the sea during the 1989 Exxon Valdez disaster. Earlier, BP's “top kill” operation to plug the ruptured well in the Gulf of Mexico failed in a stunning setback to efforts to stem the oil spill. BP and federal authorities said Saturday they are now turning to a new strategy to stop the leak. – Agencies , but it will take at least four to seven days before it can be put into place. At least 20 million gallons are now estimated to have gushed into the ocean since the disaster unfolded five weeks ago, threatening an environmental and economic catastrophe across hundreds of kilometers of the US Gulf Coast. “After three full days of attempting ‘top kill,' we have been unable to overcome the flow from the well, so we now believe it's time to move on to the next of our options,” BP Chief Operations Officer Doug Suttles told a press briefing. President Barack Obama called the developments “enraging” and “heartbreaking.” Engineers had spent days pumping some 30,000 barrels of heavy drilling fluid into the leaking well head on the ocean floor in a high-pressure bid to smother the gushing crude and ultimately seal the well with cement. But the effort failed, and when asked specifically why, Suttles had no direct answer. “We don't know that for certain,” he said. The announcement marks the latest failure for BP, which despite a series of high-tech operations over the past month has appeared powerless to bring the disaster to heel since an explosion on the BP-leased Deepwater Horizon oil rig April 20 which killed 11 workers. The rig sank two days later. The British energy giant had stressed that “top kill” was the best chance at stopping the leak other than drilling an entirely new relief well, a process that has already begun but is expected to take another two months. “Obviously, we're very disappointed in today's announcement and I know all of you are anxious to see this well secured,” US Coast Guard Rear Admiral Mary Landry told the briefing. Efforts will now focus on severing the damaged riser pipes that lay crumpled on the ocean floor, then installing a containment device that could capture the leaking oil and syphon it to the surface. The new containment plan, scheduled to begin next week, is called the “Lower Marine Riser Package Cap (LMRP Cap).” It is a complex operation that will be carried out by remotely operated robots on the ocean floor, BP officials said -- nearly one mile (1.6 kilometers) below the spot where the drilling rig exploded. The robots, wielding cutting tools, will sever the bent riser pipe and replace it with the LMRP cap, BP officials say. __
