Deborah Zabarenko, PlanetArk 5 May 10;
Oil-dispersing chemicals used to clean up the vast BP spill in the Gulf of Mexico carry their own environmental risks, making a toxic soup that could endanger marine creatures even as it keeps the slick from reaching the vulnerable coast, wildlife watchdogs say.
The use of dispersants could be a trade-off between potential short-term harm to offshore wildlife and possible long-term damage to coastal wildlife habitat if the oil slick were to reach land.
The U.S. Environmental Protection Agency has approved 14 dispersants for use on oil spills, including Corexit, manufactured by Nalco Holding Co. of Naperville, Illinois.
Corexit has been provided for use in the BP spill, and the company has exhausted its inventory and is producing more, said Mani Ramesh, Nalco's chief technology officer. Ramesh said Corexit's active ingredient is an emulsifier also found in ice cream; he disputed environmental groups' claims that it is harmful to marine life.
Nalco stock rose more than 11 percent on Monday on news that Corexit was being tested on the ocean floor near the leaking wellhead. But it retreated 2.75 percent to 25.47 on Tuesday in a broad U.S. market sell-off.
So-called dispersants work on an oil spill as dishwashing detergent works on a greasy skillet: they break up oil into tiny droplets that sink below the water's surface where naturally occurring bacteria consume them. Without dispersants, oil stays on the water's surface, where bacteria can't get at them, Ramesh said.
The problem, according to Jackie Savitz, a senior scientist at the marine environmental group Oceana, is that the dispersants themselves can be toxic to wildlife. Dispersants can also enhance oil's toxicity in the dispersion process.
This makes them simply the lesser of two bad options to fight an oil spill such as the slick created by the April 20 explosion at BP Plc's Deepwater Horizon drilling rig, she said.
"A decision is being made where it's the shore wildlife and oysters and beaches versus the animals that live in the water," Savitz said by telephone. "When they use a dispersant, it's taking the oil and essentially dissolving it in the water so that it doesn't wash up on the beach.
"It's also good for public perception, because a lot of people think it's only bad if it washes up onshore."
TURTLES, DOLPHINS AND WHALES
"Do you kill the fish or do you kill the birds?" Mark Floegel of Greenpeace asked rhetorically.
The choice may be more complex. The judgment may be that spraying these chemicals in the water column -- from the water's surface to the sea bed -- directly affects wildlife living there in the short term, but is meant to prevent the slick from reaching shore, where it could cause long-term harm to coastal wetlands and the species that live in them.
Sea turtles, dolphins and whales have been seen swimming through the oil slick, and bluefin tuna spawning grounds were not far from its southwest edge as of last Friday, according to the National Oceanic and Atmospheric Administration.
Closer to shore are oyster beds and seagrass beds -- where dolphins, birds, lobster, conch, scallops, shrimp and juvenile fish seek food and shelter -- as well as barrier island bird nests, loggerhead turtle nests, sea turtle nests and essential fish habitat, Oceana said, citing NOAA and the Unified Command working on the spill.
Allison Nyholm, a policy adviser at the American Petroleum Institute, noted that current dispersants are different from the thick solvents used in 1967 on an oil spill off the California coast at Santa Barbara.
Nyholm did not directly respond to questions about possible risks from dispersants to marine wildlife, saying there was insufficient data to make this assessment.
But she stressed that dispersants are not spread on marine life or birds: "Birds aren't naturally made to have dispersant sprayed on them. You don't want to interject a chemical reaction where you don't have to."
(Editing by Philip Barbara)
Factbox: BP's efforts to stem oil flow at seabed
Reuters 4 May 10;
(Reuters) - BP is attempting to stop the Gulf of Mexico oil spill under 5,000 feet of water using some methods that are common and others that have never been done at such water depths.
U.S. | Green Business
Here are explanations of those efforts that include details from Bob Fryar, senior vice president of BP operations in offshore Angola, and Charlie Holt, head of drilling and well completion operations in the Gulf of Mexico.
* Relief Wells
Relief wells have worked in other leaks, such as the Montara wellhead in the Timor Sea last year. But they take time. BP began drilling the first of two relief wells on Sunday, not far from the leaking well, and will drill 18,000 feet vertically and horizontally to reach the flowing well to plug it with cement and stop the flow. A second relief well is slated to begin drilling within days. The process is expected to take 60 to 90 days. At the Montara spill, where a rig leased by PTT Exploration and Production spewed oil, five relief wells had to be drilled.
* Containment chambers
In hopes of bringing quicker relief, BP will place a new steel, 73-ton, rectangular-shaped "containment chamber" atop the main leak site, where oil is leaking from a broken pipe as well as the broken drillpipe within the larger pipe. The chamber, 40 feet tall, has a funnel on top that will be connected by pipe to a drillship. Officials hope the chamber will corral leaking oil to channel to the drillship until the leak can be stopped with the relief wells. Such chambers have been used at well and pipeline leaks in much shallower waters, but never before at such depths. The chamber is expected to be in place and connected to the drillship to begin operations in seven days.
Two more chambers are being built, one to place over a third, smaller leak from a bent part of the larger pipe within two to four days of getting the first chamber in place. The third chamber is a backup.
* Close failed valves on the blowout preventer
The blowout preventer sitting atop the well on the seabed has several valves designed to automatically close off the well. Those valves, or rams, run by hydraulic controls failed on April 20.
BP did not have an acoustic control shut-off system that may have allowed it to shut a valve remotely. Such a system is not required by U.S. law.
Within 24 hours of the blowout, BP used underwater robots to try to close the valves. BP official Doug Suttles said the valves have closed, but seals have not worked.
* Valve on drillpipe to close off one of three leaks
By Tuesday BP aims to place a valve at the end of the leaking drillpipe to cut off one of three leaks. Officials do not know whether that will increase or decrease the flow of oil from the larger pipe.
* Dispersants sprayed at seabed
Spraying chemicals that break oil into smaller droplets that can later dissipate. Currently being sprayed from a wand connected to tubing at the largest plume of oil escaping from the larger pipe that contains the drillpipe. Dispersants are commonly used on oil sheens at the surface, but they have not been used before in such depths. BP began spraying at the seabed on April 30.
* New pressure control equipment
The piece of equipment sits atop the blowout preventer, called a "lower marine riser package" or LMRP. It contains mechanisms that close around the pipe containing the drillpipe. The bent and broken pipes protrude from the top of that device. BP is considering removing the LMRP and placing a new blowout preventer atop the failed one. BP will use that option only if officials determine removal of the LMRP won't worsen the leak.
(Reporting by Kristen Hays; editing by Timothy Gardner and David Gregorio)
Concerns Up and Down the Food Chain
Leslie Kaufman New York Times 5 May 10;
BRETON ISLAND, La. — As the oil spill from the Deepwater Horizon spreads across the Gulf of Mexico, environmentalists and government officials have been working frantically to protect shoreline habitat like this island in the Breton National Wildlife Refuge, eight miles off the coast of Louisiana.
Breton Island, with its hundreds of nesting birds, has been protected by orange booms, as have many other areas of delicate estuaries and wetlands.
But biologists are increasingly alarmed for wildlife offshore, where the damage from a spill can be invisible but still deadly. And they caution that because of the fluidity between onshore and offshore marine communities, the harm taking place deep at sea will come back to haunt the shallows, whether or not they are directly hit by the slick.
The gulf’s deeper water harbors 10 species of threatened sharks, 6 species of endangered turtles, manatees, whales and innumerable fish.
It is also a temporary home for the eggs of dozens of species of fish and shellfish, whose offspring spend their earliest days floating along currents at the surface of the water — the very layer where most of the oil settles.
There, the effects can be devastating, studies from previous spills show, like whales so drugged and disoriented by noxious petroleum fumes that they can drown, and tiny translucent organisms whose bodies are literally burned from the inside out as the sun heats the fuel they have ingested.
“Unfortunately, we’ve had a lot of experience in how oil affects marine life, ecosystems, coastal communities, and fisheries,” said Christopher Mann, with the marine program of the nonprofit Pew Environment Group. “The iconic images of oiled seabirds are just the tip of the iceberg, because oil spills affect life up and down the food chain.”
Take the blue crab, which, along with shrimp, is among the largest fishing crops out of Louisiana. When molting, the crabs are known as soft shells and are immensely popular in restaurants up and down the East Coast. They also serve as food for other sea creatures like redfish and certain species of turtles.
Although thought of as a coastal animal, the crabs breed at sea. As the water warms, females leave the protection of the coast for perhaps the only time in their lives and go out to shoals in the gulf to disperse fertilized eggs. The eggs hatch and billions of tiny crabs invisible to the naked eye drift for 40 days along the currents in the deep sea before ending up back in the marshes.
Many of the shoals favored by the crabs are already covered in oil, said Caz Taylor, a professor of ecology and evolution at Tulane University, who is studying their migration patterns. “It can’t be good,” she said.
Spring is mating and spawning season for almost everything in the gulf: Fill a jar with plankton from the local waters in the spring and it will typically contain the larvae of 80 species. All the eggs and hatchlings are surface dwellers, with almost no ability to swim away from the slick.
“Eggs and larvae that dwell near the sea surface are especially vulnerable,” said Jeffrey Short, Pacific research director for Oceana, a nonprofit organization that works for marine preservation.
The components of crude oil, he added, can produce developmental deformities at low concentrations, and “any such deformities are ultimately lethal to organisms in the wild.”
So far, there have been few documented animal casualties of the Deepwater Horizon spill, though rumors of dead manatees and whales abound. The National Oceanic and Atmospheric Administration said that its planes had spotted numerous species of dolphins and turtles in areas now covered by the slick.
Since Sunday, 30 turtles have washed up dead on beaches in Gulfport, Miss., an unusually high number even for this time of year when they are migrating. But Moby Solangi, executive director of the Institute for Marine Mammal Studies in Gulfport, said that in a preliminary examination, the oil did not appear to be the cause of death. Full necropsies on the animals are being completed.
Still, Michele Kelley, turtle and marine mammal stranding coordinator for Louisiana, said she is worried.
“Sea turtles are more prone to ingest the stuff,” Ms. Kelley said, especially as the slick clumps.
Whales and dolphins that must come up through the oil to get air are likely to suffer skin and eye irritation. In some cases, they may breathe in the toxic fumes of evaporation. In areas where oil is viscous, the marine mammals can risk having their skin and eyes irritated. More rarely, they risk breathing toxic fumes from the evaporating oil, and becoming drugged and sleepy.
The fumes are particularly dangerous when the crude is fresh, because some strong toxins evaporate early. With a onetime spill, the slick gets less dangerous over time, but in the gulf, where the well has not been capped, there is a constant supply of new vapors.
Dr. Solangi said he was worried for dolphins. “They have to be awake to breathe,” he said. “If they become anesthetized, they will die. If they become intoxicated by fumes, they won’t survive.”
Even normal feeding might expose sea creatures to harm from the spill: sea grass and other vegetation covered in oil are ingested by fish that are then eaten by bigger fish and finally by manatees or other marine species. It is this food-chain effect that worries Larry Schweiger of the National Wildlife Federation.
“It is not a question of whether all these species will be affected now. It is when,” he said.
States concerned about chemical dispersants
Allen Johnson Yahoo News 10 May 10;
NEW ORLEANS, Louisiana (AFP) – In the ongoing Battle of the Gulf of Mexico, the "enemy" is a gushing oil slick, fought miles from the Louisiana coast with skimming boats, controlled burns, and - amid increasing doubts -- chemical dispersants.
Rough weather last week hampered efforts to skim the oil from the sea with boats and controlled burns, but calmer waters have brought the battle back to the Gulf.
Officials are also spraying chemical dispersants over the slick to break it up, producing an effect likened to dish washing liquid.
"It's really designed to break down the oil," said Bob Perciasepe, deputy administrator of the Environmental Protection Agency (EPA).
"It does not make the oil disappear but it makes it into smaller and smaller particles that makes easier over the long haul to be biodegradable instead of big... really, oily globs."
On Saturday, three top Louisiana officials from the departments of health, environmental quality, and wildlife & fisheries published a letter to British Petroleum CEO Tony Hayward - requesting more information on the chemical dispersants.
"We have serious concerns about the lack of information related to the use of dispersants in fighting the oil spill at and below the surface of the Gulf of Mexico, and what, if any, impact the dispersants could have on our people, water and air quality, as well as the wildlife, fisheries and vegetation of Louisiana's coastline and wetlands," the state secretaries wrote on May 7.
Also, National Wildlife Federation, US environmental groups and Gulf Coast shrimpers last week raised concerns about the potential damage to marine life from both the leaking oil and chemical dispersants.
"The increasing use of dispersant has left a number of questions about where this material is moving to," said NWF chief Larry Schweiger.
Pending test results, the Environmental Protection Agency on Thursday announced a halt to BP's unprecedented, underwater use of chemical dispersants near the leaking well source -- almost a mile down (1.6 kilometers) in the chilly Gulf waters.
Huge C-130 cargo planes continued spraying chemical dispersants Saturday, carpeting vast swaths of the oil slick below.
Forty-one percent of seafood consumed in the United States comes from offshore and coastal Louisiana, Subra said, citing figures from the state Department of Wildlife & Fisheries.
Skimming is only effective when seas are one-to-three feet, BP officials have acknowledged. Controlled burning is limited to smaller, heavy concentrations of oil further south in the Gulf.
Dispersant can be sprayed at any time other than when planes can't fly, Subra says, adding that chemical dispersants are more successful with smaller spills of a fixed amount.
"But with this [Gulf] spill they have to keep applying it because the source is still there," she said.
The underwater well has been gushing an estimated 5,000 barrels of medium crude oil daily since the Deepwater Horizon sank April 22 - two days after fiery explosion left 11 crewmembers dead.
LuAnn White, a toxicologist at Tulane University, said chemical dispersants have been used on oil spills for years, including the notorious Exxon Valdez disaster in Alaska in 1989.
"What's out now is a new generation of dispersants, but we don't know what is in them because it's a ?trade secret,' White said.
NALCO Energy Services of Sugar Land, Texas, manufactures the chemical dispersant for BP, which is known by its product name "Corexit." The dispersant itself is a low-level hazardous chemical, posing risks for eye and skin irritations and "chemical pneumonia" but not cancer, according to NALCO data posted on the Deepwater Horizon web site.
"Chemical dispersants -- I come down on the ?pro' side," said Eric Smith, associate director of the Tulane Energy Institute, a finance professor and oil & gas marketing analyst.
"You are talking about a very thin dispersant. Ideally, you want to use skimmers on the heavy oil areas and dispersants on the wider sheen (of the spill)."
Rough seas are bad for skimmers but good for mixing the surface oil with dispersant - "which is like washing your hands with soap," Smith said.
Smith adds that the good news is that the spill oil is a "light sweet crude" which is easier to clean up and results in less damage than heavier crude oils.
"You may have environmental damage for a short time," Smith said, "but with this kind of crude oil, it's going to be gone in six months to a year -- if they (BP and authorities) are sticking to spraying the sheen."
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