Editor’s Note: This is part two of a three-day Herald series on the cleanup.
Take 100 to 200 million gallons of light sweet crude. Add two million gallons of industrial solvents and trade-secret chemicals. Blend 5,000 feet below the ocean surface. Spread across fragile estuaries and rich ocean waters. Stew in hot sun and hungry bacteria for three months. As a finishing touch, whip lightly in a tropical depression.
With BP finally getting a firm grasp on its gusher, the big questions in the Gulf of Mexico have rapidly turned to how, and if, an environmental mess of unprecedented scope and complexity can be cleaned up.
But with so much attention focused on the technical challenges of capping the well, federal spill managers only last week began discussing with state and parish leaders in Louisiana, the hardest hit state, how to set the standards for declaring the nation’s largest offshore oil spill officially mopped up.
“How do we get to the inevitable question of how clean is clean?” said Ret. Coast Guard Admiral Thad Allen, the Obama administration’s point man on the spill.
Many scientists and environmentalists believe there won’t be a quick or easy answer.
“We’ve never dealt with this before, the complication of this much oil coming from the deep sea and being hit heavily with chemical dispersants,” said Ron Kendall, director of the Institute of Environmental and Human Health at Texas Tech University. “We have conducted the largest environmental toxicology experiment in the history of this country in the Gulf of Mexico.”
There are some signs the experiment may not have the cataclysmic long-term ripple effects feared. Conditions have clearly and dramatically improved in the Gulf in the two weeks since BP capped its well.
A massive slick once the size of Florida has shrunk faster than anyone expected. The Coast Guard reported blue water over the Deepwater Horizon site last week and so little floating oil that skimming vessels were burning more fuel motoring around the Gulf than they were finding. Though incomplete, initial field surveys found less than 400 acres of oiled Louisiana marsh, with most oil collected along the outer fringes. Gov. Bobby Jindal even reopened some bayou waters to commercial fishing.
Terry Hazen, a microbial ecologist at the Lawrence Berkeley National Lab in California, credited the Gulf’s self-healing powers. Unlike the nutrient-lean waters of Alaska, the Gulf teems with bacteria with an appetite for oil and gas leaking from natural deep-sea seeps.
While BP and federal managers were stressing how hard it had become to find enough oil to skim, Kistner was motoring with a local fisherman through big, mostly lifeless pockets of what resembled “spongy orange cake batter” that put out an overpowering odor.
Local shrimpers, he said, worry BP’s heavy use of chemical dispersants, sanctioned by the federal government as a trade-off to keep oil from fragile marshes and off vulnerable sea birds, instead has left it to settle into fishing grounds, out of sight and mind.
“You start trawling shrimp boats through that stuff, you’re setting yourself up with a big mess,” Kistner said. “That’s going to start this whole chain reaction.”
Many scientists share the concerns. They say dispersants and submerged oil are X-factors complicating cleanup and making the prospects of a quick Gulf recovery uncertain.
BP’s blown-out well poured 10 to 20 times the volume of oil into the Gulf of Mexico than the Exxon Valdez spill. It also added 1.8 million gallons of Corexit, a dispersant federal environmental regulators acknowledge can kill or disrupt reproduction of plankton, fish and other marine life.
The oil giant’s submersible robots pumped three-quarters of a million gallons directly into the flow at the seafloor, a technique never tried or tested before that scientists suspect contributed to the massive plumes discovered extending as far as 142 miles in one direction from the blown-out well and 42 miles in another.
“That’s really the big, big issue,” said Susan Shaw, director of the Marine Environmental Research Institute in Maine. “Once you have got that dispersed oil, there is no way to clean it.”
The concentrations, ranging from .5 to .75 parts per million near the well to trace levels farther away — fall below a 1 ppm mark considered toxic for marine life. But biologists warn that exposure, particularly over time, could harm or disrupt reproduction for some marine life, particularly for plankton and larvae that form the base of the food chain.
Shaw, among a group of scientists who urged the federal government to halt dispersant use, believes the combination of oil and chemicals would be more toxic than either alone — with solvents helping oil penetrate cells.
Robert Weisberg, a professor of oceanography at the University of South Florida, whose analysis of currents helped direct colleagues to the plumes, said it could take years, and generations of fish, for scientists to assess the spill’s full impacts.
For now, he said, it’s only a guess how much oil may be down there and whether it’s harmless or harmful.
“We are operating out of ignorance,” he said. “It may be no threat whatsoever or it may be a serious threat. The concentrations are low but we’re talking about a very large area.”
Federal cleanup commanders stress that they’re committed to capturing every barrel possible — and getting BP to pay for it. With slicks harder to find at sea, they’re shifting local boats from skimming to tar-ball patrols, a job Allen predicted would continue for at least four to six weeks.
Oceanographer Hans Graber, director of the University of Miami’s satellite sensing facility, expects oil problems to persist long after the last skimmer has docked and the last boom picked up, decontaminated and packed away.
“It’s probably a fair guess to say we’re looking at years, if not tens of years, for all of this stuff to eventually come to the surface.”