U.S.

Engineers "Trying Anything" to Stop Oil Spill

May 10, 2010 / 7:05 AM EDT / CBS/AP

Updated 3:30 p.m. ET

A remote-controlled submarine shot a chemical dispersant into the maw of a massive undersea oil leak Monday, further evidence that authorities expect the gusher to keep erupting into the Gulf of Mexico for weeks or more.

Crews using the deep-sea robot attempted to thin the oil — which is rushing up from the seabed at a pace of about 210,000 gallons per day — after getting approval from the Environmental Protection Agency, BP spokesman Mark Proegler told The Associated Press.

The agency had halted two previous rounds of the dispersant to test its potential impact on the environment, and approved a third round of spraying that began early Monday, Proegler said.

Complete Coverage: Disaster in the Gulf

The EPA said in a statement the effects of the chemicals were still widely unknown.

BP engineers, casting about after an ice buildup thwarted their plan to siphon off most of the leak using a 100-ton containment box, pushed ahead with other potential short-term solutions, including using a smaller box and injecting the leak with junk to plug it. However, none of these has been tried so deep — about a mile down. Workers were simultaneously drilling a relief well, the solution considered most permanent, but that was to take up to three months.

On land a major sandbag airlift got underway Monday in Louisiana. Blackhawk helicopters are picking up sandbags to fly them to be dropped on five points east of Port Fourchon. The project is aimed at protecting Lafourche Parish marshes from the massive oil slick.

The spill began creeping farther west of the Mississippi River last week.

As for the solution at sea, BP PLC officials said they were considering several options to stop the daily rush of at least 200,000 gallons of crude from the blown-out well a mile underwater. BP PLC spokesman Mark Proegler said no one has settled on what step the company will take next, but a decision could come by Monday.

With crippled equipment littering the ocean floor, engineers from the oil company - which is responsible for the cleanup - scrambled to devise a fresh method to cap the ruptured well. Their previous best hope for containing the leak quickly, a four-story containment box, became encrusted with deep-sea crystals Saturday and had to be cast aside.

Among the plans under consideration:

- Deploying a new, smaller containment box in the hope that it would be less likely to get clogged. Officials said the new box could be in place by midweek.

"We're going to pursue the first option that's available to us and we think it'll be the top hat," the smaller box, BP Chief Operating Officer Doug Suttles said.

- Cutting the riser pipe, which extends from the mile-deep well, undersea and using larger piping to bring the gushing oil to a drill ship on the surface, a tactic considered difficult and less desirable because it will increase the flow of oil.

- Shooting mud and concrete directly into the well's blowout preventer, a device that was supposed to shut off the flow of oil after a deadly April 20 oil rig explosion but failed. The technique, known as a "top kill," is supposed to plug up the well and would take two to three weeks.

"The next tactic will be a junk shot," Coast Guard Adm. Thad Allen told "Face the Nation" anchor Bob Schiffer on Sunday. "They'll take a bunch of debris, shredded up tires, golf balls and things like that and under very high pressure shoot it into the preventer itself and see if they can clog it up and stop the leak."

- CBS News correspondent Don Teague reports that BP is also considering using deep sea dredges to try and pile up sand near the coastline to build artificial barrier islands. The hope is that the new islands might absorb much of the crude before it can impact the sensitive marshlands on southern fringe of the Gulf states.

The engineers appear to be "trying anything people can think of" to stop the leak, said Ed Overton, a LSU professor of environmental studies.

An estimated 3.5 million gallons of oil have spilled since an explosion on April 20 on the drilling rig, the Deepwater Horizon, 50 miles off the Louisiana coast. At that pace, the spill would surpass the 11 million gallons spilled in the Exxon Valdez disaster by next month. BP is drilling a relief well that is considered a permanent fix, but that could take months to complete.

Above the oil leak, waves of dark brown and black sludge crashed into the support ship Joe Griffin. The fumes there were so intense that a crew member and an AP photographer on board had to wear respirators while on deck.

At least 3.5 million gallons were believed to have leaked since an April 20 drilling rig blast killed 11. If the gusher continues unabated, it would surpass the Exxon Valdez disaster as the nation's worst spill by Father's Day.

Engineers appear to be "trying anything people can think of" to stop the leak, said Ed Overton, a LSU professor of environmental studies.

Authorities also planned to use south Louisiana's system of locks and levees to release water to help keep the worst of the oil at sea.

"We're trying to save thousands of acres of marsh here in this area, where the shrimp lay their eggs, where the fin fish lay their eggs, where the crabs come in and out," said Chett Chiasson, executive director of the Greater Lafourche Port Commission. "We're trying to save a heritage, a way of life, a culture that we know here in recreational and commercial fishing."

BP — which is responsible for the cleanup — said Monday the spill has cost it $350 million so far for immediate response, containment efforts, commitments to the Gulf Coast states, and settlements and federal costs. The company did not speculate on the final bill, which most analysts expect to run into tens of billions of dollars.

Among plans under consideration for the gusher, BP is looking at cutting the riser pipe, which extends from the well, undersea and using larger piping to bring the gushing oil to a drill ship on the surface, a tactic considered difficult and less desirable because it will increase the flow of oil.

Philip Johnson, a petroleum engineering professor at the University of Alabama, said cutting the riser pipe and slipping a larger pipe over the cut end could conceivably divert the flow of oil to the surface.

"That's a very tempting option," he said. "The risk is when you cut the pipe, the flow is going to increase. ... That's a scary option, but there's still a reasonable chance they could pull this off."

Johnson was less optimistic that a smaller containment box would be less susceptible to being clogged by icelike crystals.

"My suspicion is that it's likely to freeze up anyway," he said. "But I think they should be trying everything they can."

Teague reports the urgency to contain the spill grew over the weekend as the first blobs of crude oil began washing ashore.

Dime- to golfball-sized balls of tar washed up Saturday on Dauphin Island, three miles off the Alabama mainland at the mouth of Mobile Bay and much farther east than the thin, rainbow sheens that have arrived sporadically in the Louisiana marshes. Until Saturday none of the thick sludge - those indelible images from the Valdez and other spills - had reached shore.

Oil — be it a surface sheen, globules or balls of tar — has washed up west of the Mississippi River and as far east as Dauphin Island, three miles off the Alabama mainland at the mouth of Mobile Bay.

The blowout aboard the rig, which was being leased by BP, was triggered by a bubble of methane gas that escaped from the well and shot up the drill column, expanding quickly as it burst through several seals and barriers before exploding, according to interviews with rig workers conducted during BP's initial, internal probe. The exact cause remains under investigation.