PENSACOLA, Florida — The British Petroleum oil slick drifted perilously close to the Florida Panhandle's famous sugar-white beaches Wednesday as a risky gambit to contain the leak by shearing off the well pipe ran into trouble 1.6 kilometers under the sea when the diamond-tipped saw became stuck.BP representatives said the saw was about halfway done slicing through the pipe when the diamond-tipped saw snagged, adding that it took 12 hours to free the saw and that preparations were underway to resume cutting.The plan is to fit a cap on the blown-out well at the bottom of the Gulf of Mexico to capture most of the spewing oil; the twisted, broken pipe had to be sliced first to allow a snug fit."I don't think the issue is whether or not we can make the second cut. It's about how fine we can make it, how smooth we can make it," said Coast Guard Adm. Thad Allen, the government's point man for the crisis.Allen said more staff, boats and helicopters were sent to the eastern Gulf Coast as the slick spread. The boats will help skim oil and add more protective boom to collect it. Four helicopters would help skimmers spot threatening oil.As the edge of the slick drifted within 11 kilometers of Pensacola's beaches, emergency workers rushed to link the last in a kilometers-long chain of booms designed to fend off the oil. They were stymied by thunderstorms and wind before the weather cleared in the afternoon.Forecasters said the oil would probably wash up by Friday, threatening a delicate network of islands, bays and white-sand beaches that are a haven for wildlife and a major tourist destination dubbed the Redneck Riviera. "We are doing what we can do, but we cannot change what has happened," said John Dosh, emergency director for Escambia County, which includes Pensacola.Since the biggest oil spill in US history began to unfold April 20 with an explosion that killed 11 workers aboard an offshore drilling rig, crude has fouled some 200 kilometers of Louisiana coastline and washed up in Alabama and Mississippi as well. Over the past six weeks, the well has leaked anywhere from 80 million liters to 170 million liters by the government's estimate.The latest attempt to control the leak is considered risky because slicing away a section of the 50-centimeter riser could remove kinks in the pipe and temporarily increase the flow of oil by as much as 20 percent. The cap could be placed over the spill as early as Wednesday.If the strategy fails — like every other attempt to control the leak 1,524 meters underwater — the best hope is probably a relief well, which is at least two months from completion.As the oil drifted closer to Florida, beachgoers in Pensacola waded into the gentle waves, cast fishing lines and sunbathed, even as a two-man crew took water samples. One of the men said they were hired by BP to collect samples to be analyzed for tar and other pollutants.Officials said the slick sighted offshore consisted in part of "tar mats" about 152 meters by 610 meters in size.County officials set up the booms to block oil from reaching inland waterways but planned to leave beaches unprotected because they are too difficult to defend against the action of the waves and because they are easier to clean up."It's inevitable that we will see it on the beaches," said Keith Wilkins, deputy chief of neighborhood and community services for Escambia County. Florida's beaches play a crucial role in the state's tourism industry. At least 60 percent of vacation spending in the state during 2008 was in beachfront cities. Worried that reports of oil would scare tourists away, state officials are promoting interactive Web maps and Twitter feeds to show travelers — particularly those from overseas — how large the state is and how distant their destinations may be from the spill."I'm going to be bankrupt very soon," said fisherman Hong Le, who came to the US from Vietnam and rebuilt his home and business after Hurricane Katrina in 2005 wiped him out. "Everything is financed. How can I pay? No fishing, no welding. I weld on commercial fishing boats and they aren't going out now, so nothing breaks."