Jeanna Bryner, livescience.com 30 Apr 10;
BP is attacking the oil spill in the Gulf of Mexico on all fronts, from the traditional skimmers and booms to more advanced technologies. But history and science suggest this clean-up effort probably won't end in a spotless environment.
BP Chief Executive Tony Hayward said the company would do "everything in our power to contain this oil spill and resolve the situation as rapidly, safely and effectively as possible," according to news reports. The company, which was leasing the Transocean oil rig that exploded and sank on April 22 in the Gulf, is responsible for the clean-up.
And yes, all hands are on deck - skimmers, booms, domes, controlled burning and chemical dispersants - to try to clean up the 1,000 to 5,000 barrels a day estimated to be leaking out of the well.
However, for an oil spill at sea, typically only 10 to 15 percent of the oil is recovered, Gerald Graham, president of Worldocean Consulting, a marine oil spill prevention and response planning firm based in British Columbia, told LiveScience.
So far, BP claims it has recovered 685,062 gallons (more than 2.5 million liters) of an oil-and-water mix. That mix is almost entirely water, with oil stirred in like vinaigrette. Until the entire recovery process finishes, it will be impossible to tell how much crude oil BP has recovered, Graham said.
The rest of the oil that doesn't get cleaned up evaporates, breaks up and floats on the surface, or sinks to the bottom, Graham said.
"It's kind of overwhelming," U.S. Coast Guard Petty Officer 3rd Class Cory Mendenhall said of the cleanup effort.
"A lot of it cannot be collected," Mendenhall said. "95 percent [of the oil] is a rainbow-y sheen. It's too thin to scoop up. Most of that breaks up naturally, so about 3 percent of the oil is what people think of as big globs of oil that you can skim off the water. Now, how much of that 3 percent has been collected is still unsure."
History attests to the lingering problem of oil spills. Exxon Valdez, one of the worst oil spills ever, dumped more than 10 million gallons of crude into Prince William Sound, Alaska, on March 24, 1989. And there's still a lot of oil that didn't get cleaned up, which has continued to impact wildlife in the area for the past 20 years, experts say.
"Despite spending $2 billion dollars and using every known clean-up method there was, they recovered 8 percent of the spilled Exxon Valdez oil," said Jeffrey Short, Pacific science director for Oceana, a Washington, D.C.-based ocean conservation organization. "That is typical of these exercises when you have a large marine oil spill. You're doing really great if you [get] 20 percent."
Cleanup under way
So far, the most effective method has been chemical dispersants. Least effective: booms, according to Mendenhall. Here's what's being done to capture the oil:
Chemical dispersants: About 100,000 gallons of chemical dispersant has been dropped from the air into the Gulf, where it breaks up the oil slick into smaller droplets. The droplets then get mixed into the water, where they are subjected to ocean currents and natural degradation processes, according to the Minerals Management Service (MMS). "This potentially exposes the water column and near shore shallow bottom-dwelling organisms to oil," according to MMS.
Skimmers: Once broken up, skimming vessels come in and collect what's left. The droplets are collected in drums and some of that material gets cleaned and recycled. The rest is "properly disposed," Mendenhall said. But skimmers can only capture about 10 percent of the volume of spilled oil, according to Charlie Henry of the National Oceanic and Atmospheric Administration (NOAA).
Controlled burn: On Wednesday, BP and the Coast Guard, along with other agencies, conducted an in-situ burn in which they used a fireproof boom to corral dense parts of the oil spill, moving it to another location and then burning it.
In general, burning is probably the most effective method for cleaning up heavy oil like that leaking in the Gulf, according to said Edward Overton, a professor emeritus of environmental sciences at Louisiana State University. But it has drawbacks. When you burn near the coast, you have to destroy wildlife, and offshore burning is harder to do.
"I have no idea what we're going to do, this is trial and error to see what works and what doesn't work," Overton said. And news reports suggest since the oil is really an oil-water mix, burning actually might not do the trick.
Collection domes: BP has also started to put together a subsea oil collection system, and when used will be the first time this shallow-water technology has been adapted for the deep water. The oil leaks in the Gulf are nearly a mile down. It is expected to be ready for deployment within the next four weeks, according to BP.
When ready, here's how the oil-spill technology would work: The dome would be placed on the seabed to capture the leaking oil. This oil would then be pumped up to surface vessels that could collect the oil and take it away. Similar systems have been used in shallow water, but never at depth of 5,000 feet. The Coast Guard has said the construction could take two to four weeks.
New method: However, Thursday afternoon officials said they might try an experimental oil-dispersal method that would involve releasing chemicals from under the water. "We were notified that this technique might be more effective in spreading the dispersant at the source on the riser than by using aircraft to spread it on the sea," said Doug Suttles, BP's Chief Operating Officer.
Leftover oil
As for what happens to the "dispersed oil," that doesn't get skimmed off or burned off or otherwise collected, "We're told it disperses naturally. It eventually breaks up and evaporates. There are different ways, but we're told it just kind of goes away," U.S. Coast Guard's Mendenhall said.
Bacteria can also help degrade most components of oil.
But not all oils are created equally. At first, reports suggested the oil leaking into the Gulf was standard Louisiana crude oil, a type of oil that biodegrades pretty well, Overton said. But sample testing revealed that the leaking oil was a different type, one that contains a very high concentration of components that don't degrade easily, called asphaltenes, according to Overton. He estimates that the concentration of these asphaltic components could be as high as 50 percent in this oil spill, while in other types of crude oil it might be as low as 1 or 2 percent.
"That is bad, bad news, because this oil is going to be very slow to degrade," Overton said today.
Some of the oil sinks to the sea bottom, where it can get buried into an anaerobic zone where there's no oxygen. Oil in these zones stays in a chemically reduced form and doesn't degrade as much, Overton said. But, he added, there's not much life down there to be contaminated.
The oil slick could reach the Mississippi Delta coast as early as Friday, so at least some oil will hit shore. A satellite image of the slick taken Thursday showed it was almost touching the delta.
History as a guide
The 1989 Exxon Valdez spill that fouled over 1,200 miles (1,900 kilometers) of shoreline in Alaska in 1989 has shown that once an oil slick makes landfall and soaks into the beach, it can take decades for the pollution to break down and disappear. About 40 percent of the 10.8 million gallons spilled reached shore in Prince William Sound, according to Short.
"There's still a lot of oil that didn't get cleaned up," from the area around Prince William Sound where the spill occurred, said Daniel Esler, a University Research Associate, based at the Centre for Wildlife Ecology at the Simon Fraser University in British Columbia, Canada.
Some beaches didn't get cleaned up as much as others, and certain coastal environments (with particular types of sediments and patterns of water flow) tend to hold on to the oil for longer than others. While it can't be seen if you walk along the beach, digging down into the sediments at certain spots can lead to pools of oil that remain in much the same condition as when they first spilled.
For instance, in 2001, 2003 and 2007, researchers dug over 12,000 pits at dozens of beach sites that had been covered in oil back in 1989. The team found black, oily liquid in over half of the holes dug in 2001.
This subsurface oil was "fingerprinted" back to the Exxon Valdez as the ultimate source (the star-crossed region also had an earthquake-caused oil spill back in 1964). This hidden oil contained the same proportions of polycyclic aromatic hydrocarbons in it as the Exxon Valdez oil collected right at the initial time of the spill. "There was no question we were looking at Exxon Valdez oil," Short, who led the three surveys, told Livescience.
The lingering oil estimate for affected Alaskan beaches stood at 21,000 gallons (80,000 liters) in 2004. This Exxon Valdez oil is decreasing at a rate of 0 to 4 percent per year according to the Exxon Valdez Oil Spill Trustee Council (EVOSTC) - though the lower rate is much more likely - meaning it will take decades or even centuries for the oil to disappear entirely.
Though the lingering oil has broken down, in some locations it remains almost as toxic to the environment as the freshly spilled variety, according to EVOSTC's Web site. (EVOSTC oversees restoration use of civil money to clean up the Sound.)
And even though this leftover oil is "just a teeny fraction of what was originally spilled," Esler said, certain species can still be exposed to it.
Esler and his colleagues used a biomarker that indicates exposure to hydrocarbons (of which oil is one) to look at the potential exposure of harlequin ducks, a particularly vulnerable species, in the area affected by the spill. They found that these ducks were coming into contact with the spilled oil even 20 years after the incident.
Take-home
The findings suggest that oil spills can have an impact on the environment for much longer than previously thought, even decades later.
In the case of the Gulf spill, the oil won't last as long if it stays in open ocean - there it will either evaporate or congeal into clumps and sink to the ocean floor, Esler explained. But if it reaches the coast, it could encounter the types of environments where it can stick around for a long time.
Given the number of places where oil spills have happened and oil has remained even after clean-up efforts, "it's not unreasonable" to think that oil could remain for some time if reaches the Gulf coast, Esler said in a telephone interview Thursday.
The situation at Prince William Sound isn't all bad though, as it seems some species are out of the woods in terms of exposure threats and "there are lots of hints that things are getting better," Esler said.
Oil spill fans fears of fishery, tourism damage
Evelina Shmukler, Reuters 30 Apr 10;
PASS CHRISTIAN, Mississippi (Reuters) - Fishermen and tourism businesses in the northeast Gulf of Mexico are dreading the nightmare possibility that a huge oil spill could wreck their livelihoods if it reaches shore.
The threat could not come at a worse time as the oyster season ends and shrimp season is set to begin.
For Joe Jenkins, owner of Crystal Seas Oysters, an oyster and shrimp processing factory in the picturesque Mississippi coastal town of Pass Christian, there is little option but to wait and hope disaster does not strike.
"It's time for the little shrimp to start coming out so we can catch those guys," Jenkins said. "An oil spill will kill all of those guys."
Around 100 boats work out of Pass Christian, one of the busiest harbors on the Mississippi Gulf Coast.
As the Coast Guard and oil company BP Plc struggle to contain the slick from a blown-out well off Louisiana, states to the east were deploying fire-retardant booms and other measures to protect their coastlines.
The slick, five times bigger than first thought, threatens the eastern shores of Louisiana and could also affect coastal waters in Mississippi, Alabama and northwest Florida.
The Southern Shrimp Alliance told the National Marine Fisheries Service in Washington this week it could help with prevention and clean-up.
"They are willing to pull booms if they have to," said Deborah Long, a spokeswoman for the non-profit trade alliance. "The timing of this could be horrible."
U.S. landings of shrimp were valued at $442 million in 2008, up 2 percent from the previous year, according to the National Marine Fisheries Service.
But the industry has been hammered by cheap imports and falling international prices, Long said.
At this time of year, shrimp head out to sea from inland estuaries where they spawn. The industry fears a southerly wind could keep oil off the coast but push the shrimp into the slick, Long said.
THREAT TO TOURISM, ECOLOGY
The slick could also hit the tourism sector that is vital to Gulf Coast economies.
In Alabama, coastal residents and businesses were "frantic" about the possible impact if the slick was blown east, said George Crozier, director of the Dauphin Island Sea Lab, a state marine research facility.
Tourists spent $2.3 billion on Alabama's beaches in 2008, supporting 41,000 workers, according to the Alabama Gulf Coast Convention and Visitors Bureau.
But Alabama's beaches would be easier to clean than salt marshes and oyster reefs. Crozier said the state's oyster fisheries are in "immediate jeopardy."
"If they can't stop it and we wind up dealing with a flow of oil for three months, that carries us into hurricane season and all bets are off because it becomes a very significant ecological problem," he said.
The spill could also fracture a fragile relationship between Louisiana's powerful energy lobby and environmental groups that say decades of exploration have hurt the coastline.
Coastal Louisiana sits on the Mississippi Delta and environmentalists say inland oil and gas exploration and the building of pipelines and canals have eroded wetlands.
That loss exacerbated the storm surge in Louisiana that devastated New Orleans during Hurricane Katrina in 2005 and an oil spill will do further harm, said Steven Peyronnin, executive director of the Coalition to Restore Coastal Louisiana.
"We have a catastrophe on our hands right now. This is a moment to change policy, to really look at the risk we have undertaken here for a century and make changes," he said.
"The state's greatest challenge is to find a way to harmonize safe, effective (oil and gas) production to maintain the state's engine and to recognize the natural system as important to the state as well."
But restoring wetlands would cost big money. Estimates even before Katrina stood at $14 billion, Peyronnin said.
(Additional reporting by Kelli Dugan in Alabama; Writing by Matthew Bigg; Editing by Pascal Fletcher and John O'Callaghan)
Oil slick expected to hit coast reserve Thursday
Chris Baltimore, Reuters 29 Apr 10;
HOUSTON (Reuters) - A massive oil slick from a blown-out well in the Gulf of Mexico is expected to reach a Louisiana wildlife reserve on Thursday as it threatens an environmental disaster across four southern U.S. states.
The rig accident, which has pounded the share prices of energy giant BP Plc and other companies involved in the project, may also have ramifications for proposals in Congress and by President Barack Obama to issue new offshore drilling permits.
Obama said London-based BP was ultimately responsible for the cost of the cleanup but that his government would "use every single available resource" -- including the military -- to address the spill.
Louisiana, still recovering from the ravages of Hurricane Katrina in 2005, declared a state of emergency as the growing slick appeared to be coming ashore much sooner than predicted.
"We are expecting to see the first impact at Pass-a-Loutre (Wildlife Management Area) today, Chandeleur Islands on Saturday," said Louisiana Governor Bobby Jindal.
The Coast Guard said the edge of the slick was just 3 miles from the Pass-a-Loutre reserve, a maze of waterways, marsh and sandbanks on the edge of the Mississippi Delta.
Earlier at a briefing in Washington, Coast Guard Rear Admiral Sally Brice-O'Hare had predicted the leading edge of the slick would make landfall in the Mississippi Delta "sometime" on Friday.
The leak, after a rig leased by BP exploded last week, is spewing five times more oil than previously estimated and raising fears of severe damage to fisheries, wildlife refuges and beaches in Louisiana, Mississippi, Alabama and Florida.
"This is a spill of national significance," Janet Napolitano, the secretary of Homeland Security, told a news conference at the White House. "We will continue to push BP to engage in the strongest response possible."
Bill Nelson, a Democratic senator from Florida, said he was filing a bill to temporarily prohibit the administration from expanding offshore drilling, citing the risk of a potential "environmental and economic disaster" from the spill.
SHIPPING AND DRILLING
Cameron International Corp, which supplied the blowout preventer for the rig, said on Thursday it was insured for $500 million of liability, if needed. Halliburton said it did a variety of work on the rig and was assisting with the investigation.
Shrimp fishermen in Louisiana filed a class-action lawsuit against BP, Transocean, Halliburton and Cameron late on Wednesday, accusing them of negligence. None of the companies had an immediate comment on the lawsuit.
The White House said Obama has been briefed on how the slick may interfere with shipping channels, which it said could affect tankers delivering petroleum to the U.S. market.
It was not immediately clear to what extent shipping in the Gulf could be affected. While the Mississippi is a major export route for U.S. grains and the region is a significant importer of crude oil, there were no reports of disruptions.
The Louisiana Offshore Oil Port, which handles more than 1 million barrels a day of crude imports and is connected by pipeline to the biggest U.S. refining region, said it did not expect any effect on its operations, which remained normal.
But there are signs the spill will be worse than one in 1969 off Santa Barbara, California, that prompted a moratorium on oil and gas drilling off the Pacific and Atlantic coasts -- a ban Obama has said he wants to modify.
The Obama administration did not rule out imposing a pause in new deepwater drilling until oil companies can show they can control any spills that may happen.
"Everything is on the table," Deputy Interior Secretary David Hayes told reporters before Senator Nelson announced his legislation, adding it could take 90 days to install a relief valve to stop the leak.
STRUGGLE TO CONTAIN SLICK
Eleven workers are missing and presumed dead after the rig disaster, the worst in the United States in almost a decade.
Transocean's Deepwater Horizon rig sank on April 22, two days after it exploded and caught fire while the company was finishing a well for BP about 40 miles southeast of the mouth of the Mississippi River.
The daily leak from the well blowout is now estimated at 5,000 barrels or about 210,000 gallons (795,000 liters).
The Navy said it was supplying the Coast Guard with inflatable booms and seven skimming systems.
BP and the Coast Guard have mounted what the company calls the largest oil spill containment operation in history, involving dozens of ships and aircraft. But they are struggling to control the slick from the leaking well 5,000 feet (1,525 meters) under the sea off Louisiana's coast.
After underwater robots failed to activate a cutoff valve to stop the leak, BP and the Coast Guard set a "controlled burn" on Wednesday to try to prevent the slick from growing.
(Editing by Pascal Fletcher and John O'Callaghan)
Factbox: Other major marine oil spills
Reuters 29 Apr 10;
(Reuters) - A widening oil spill off the Gulf coast was expected to make landfall on Friday evening and the White House declared the spill an incident of national significance.
Following are some of the world's major marine oil spills:
1991 - During the Gulf War, Iraqi forces opened valves and destroyed oil facilities in Kuwait, releasing about 520 million gallons (1.9 billion liters) of oil, creating a slick that covered some 4,000 square miles (10,360 square km) in the biggest spill in history.
1989 - The Exxon Valdez ran aground on a reef in Alaska's Prince William Sound, spilling 10.8 million gallons (40.8 million liters) of oil. It polluted more than 1,100 miles of coastline and devastated wildlife in the largest spill in U.S. history.
1983 - In the gulf off Iran, a tanker struck a drilling platform which collapsed into the sea, releasing some 80 million gallons (303 million liters) before it was repaired.
1983 - The Castillo de Bellver sanks off the South African coast, spilling 79 million gallons (300 million liters) of oil.
1979 - A Greek oil tanker collided with another ship during a tropical storm, spilling 90 million gallons (340 million liters) of crude oil off the coast of Trinidad and Tobago.
1978 - The Ixtoc exploratory well blew out in the Bay of Campeche off Ciudad del Carmen, Mexico. By the time it was brought under control almost a year later, it spilled some 140 million gallons (530 million liters) of oil into the bay.
1978 - The Amoco Cadiz ran aground off the coast of Britanny, France, spilling its entire cargo of 69 million gallons (260 million liters) of oil and polluting 200 miles of coastline.
1967 - The Torrey Canyon, one of the first oil supertankers, hit a reef and spilled 31 million gallons (117 million liters) of crude oil in the sea between England and France in the first major oil spill. It contaminated about 180 miles of coast, and many of the attempted measures to clean up the slick proved more deadly to wildlife than the oil.
(Editing by Xavier Briand)
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