Updated

PORT FOURCHON, La. -- The 40-foot-long corrugated steel boxes, resembling oversized white shipping containers, are stacked two high and three wide atop a barge at Port Fourchon, the oil industry's hub on the Gulf of Mexico. The words "Martin Quarters" painted in black offer the only clue that they're not stuffed with cargo.

This barge is a floating hotel, or "flotel," set up by BP and several subcontractors to accommodate more than 500 workers hired to clean up the worst oil spill in U.S. history. Temporary housing is the only way to station workers at Port Fourchon, a massive shipyard that serves offshore oil rigs and is surrounded by ecologically sensitive marshes and beaches.

"There are no permanent residents here on the port," said Dennis Link, a manager from a BP refinery who's handling logistics at the 1,300-acre site that's easily accessible by ship, but reachable on land only by a state road that snakes through the bayous.

With the ambitious "top kill" having failed over the weekend and a relief well at least two months away, BP was ramping up its efforts to clean up the Louisiana coast. Another temporary fix -- an effort to saw through the pipe leaking the oil and cap it -- could be tried as soon as Wednesday. In the meantime, more than 125 miles of the state's coastline already have been hit with oil, including the resort of Grand Isle near Port Fourchon.

Shares in BP PLC were plunging in London on Tuesday after the oil company's latest failed attempt to block the oil leak in the Gulf. Shares fell 13 percent to $6.20 on the London Stock Exchange. Tuesday was the first day of trading there since the failed attempt over the weekend.

BP also said costs for the spill have reached $990 million.

The cleanup, relief wells and temporary fixes were being watched closely by President Barack Obama's administration. Obama planned to meet for the first time Tuesday with the co-chairmen of an independent commission investigating the spill, while Attorney General Eric Holder was headed to the Gulf Coast to meet with state attorneys general.

On Monday afternoon, the living quarters on the flotel sat empty. Generators pumped in cool air and powered the lights, and at the foot of each bunk sat a towel, washcloth and individually wrapped bar of soap. If necessary, four tents on dry land nearby can house 500 more workers. Workers will likely be trucked in on the two-lane state road.

The accommodations on the barge are Spartan, but comfortable -- similar to military barracks. Each pod contains 12 bunks, with a bathroom for every four. Per Coast Guard standards, each resident gets 30 square feet of space in the quarters. The barge has 10 washers, 10 dryers and a kitchen, although food will be served in a tent on land. The quarters are typically floated alongside offshore oil rigs to supplement housing on the drilling operations.

The flotel could be moved if significant amounts of oil wash up at another location. Another flotel sits about 15 miles away, off Grand Isle, and BP plans to establish them elsewhere along the coast. Port Fourchon and Grand Isle were quiet Monday, with only a handful of people seen walking on the beaches by an Associated Press reporter and photographer flying over in a helicopter.

BP is hiring local workers and ones from other states, and Link acknowledged that some from Louisiana might prefer a long drive home each to staying on the flotel.

For Chad Martin, co-owner of Martin Quarters, business is booming. His company has 200 living quarters, and 60 were available when a BP subcontractor called. The oil giant rented every single one.
But Martin understands the gravity of the situation.

"This is not the way to get work," he said

Cleanup efforts are being ramped up while BP also tries the latest in a series of patchwork fixes, this one a cut-and-cap process to put a lid on the leaking wellhead so oil can be siphoned to the surface. The risky procedure could, at least temporarily, increase the oil flowing from the busted well.

Using robot submarines, BP plans to cut away the riser pipe this week and place a cap-like containment valve over the blowout preventer. On Monday, live video feeds showed robot submarines moving equipment around and using a circular saw-like device to cut small pipes at the bottom of the Gulf.

"We are well into the operation to put this cap on the well now," BP Managing Director Bob Dudley told NBC's "Today" show on Tuesday.

BP failed to plug the leak Saturday with its top kill, which shot mud and pieces of rubber into the well but couldn't beat back the pressure of the oil.

The oil company also announced plans Monday to try attaching another pipe to a separate opening on the blowout preventer with some of the same equipment used to pump in mud during the top kill. The company also wants to build a new freestanding riser to carry oil toward the surface, which would give it more flexibility to disconnect and then reconnect containment pipes if a hurricane passed through.

Neither of those plans would start before mid-June and would supplement the cut-and-cap effort.

But the best chances for sealing off the leak are two relief wells, the first of which won't be ready until August. The spill has already leaked between 19.7 million and 43 million gallons, according to government estimates.

For the relief well to succeed, the bore hole must precisely intersect the damaged well, which experts have compared to hitting a target the size of a dinner plate more than two miles into the earth. If it misses, BP will have to back up its drill, plug the hole it just created, and try again.

"The probability of them hitting it on the very first shot is virtually nil," said David Rensink, incoming president of the American Association of Petroleum Geologists, who spent most of his 39 years in the oil industry in offshore exploration. "If they get it on the first three or four shots they'd be very lucky."

The trial-and-error process could take weeks, but it will eventually work, scientists and BP said. Then engineers will then pump mud and cement through pipes to ultimately seal the well.

On the slim chance the relief well doesn't work, scientists weren't sure exactly how much -- or how long -- the oil would flow. The gusher would continue until the well bore hole collapsed or pressure in the reservoir dropped to a point where oil was no longer pushed to the surface, said Tad Patzek, chair of the Petroleum and Geosystems Engineering Department at the University of Texas-Austin.

BP said it doesn't know how much oil is in the reservoir because it was starting to collect and analyze data on its size when the rig exploded April 20.

In Patzek's mind, failing to get the relief wells to work isn't an option.

"I don't admit the possibility of it not working," he said.