When BP’s Deepwater Horizon oil rig exploded in the Gulf of Mexico last month, phones started ringing at the desks of federal scientists 2,200 miles away on the shores of Seattle’s Lake Washington. Five weeks later, they’re still ringing. The scientists at NOAA’s Office of Response and Restoration, or OR&R, are the nation’s experts on oil spills. They attempt to quickly analyze what is at risk, and then advise the Coast Guard and other agencies what to do about it. In a typical year, they deal with up to 200 spills, large and small, ranging from a beached barge on the Florida coast to a leaky pipeline on Alaska’s North Slope. Some have been at this job for more than 20 years, dating back to before the infamous Exxon Valdez spill of 1989. Like most scientists, they prefer to work quietly, leaving the press conferences and politics to state and local officials closer to the scene. Their job is to quickly apply science and experience to the immediate crisis, unfettered by oil politics or environmental passions. But the BP crisis soon became an oil spill in a league of its own, creating ugly and enormous challenges that didn’t fit OR&R’s playbook. The initial explosion and fire killed people. It happened a mile underwater. It was big, getting bigger by the hour, and they had no way to measure how big. And suddenly, those mild-mannered scientists found themselves in the middle not just of an oil spill, but of a national media storm that was morphing into a political war zone. In particular, they’ve been accused, by no less than the New York Times, of systematically understating the amount of oil that is gushing into the Gulf. “It’s the numbers game,” says Doug Helton, who has had to deal with the press and politics while his colleagues deal with the oil. “I’ve learned a lot about the media age we’re in.” It began April 20 as a “search and rescue” problem, Helton says. The rig was on fire, 11 oil workers were missing, and the platform included a storage tank filled with diesel fuel. The next day, the rig sank in 5,000 feet of water, and oil started gushing from broken pipes at the bottom. Since then, the OR&R staff has worked virtually round-the-clock. They have command posts in Louisiana and Alabama, all linked into the windowless “War Room” in Seattle. Retired scientists have come back to help out. But they’ve been stymied by the sheer scale, depth, and vast uncertainties swirling with that oily plume. Here’s a glimpse at some of the challenges: Numbers While the initial estimate was 5,000 barrels per day, the NOAA experts knew it could be much larger. Early on, somebody scribbled the figure “64k-110k bbls/day” on a whiteboard, which was caught on a visitor’s video. Critics took this as evidence that NOAA knew the leak was much worse than the official estimate, but was concealing the bad news. That notation was a “worst case scenario,” Helton says, scribbled during an early-morning briefing. Ultimately, the actual volume may prove to be that bad. “At some point, the actual volume doesn’t matter,” he says. “We don’t know the number, and if we did there is nothing we would do any differently.” More important, he says, is the difference between a leaking tanker and a blown oil rig. “A tanker has a finite volume. You can reach out and touch it.” But the leaking pipe just keeps gushing oil, under pressure, day by day until somebody figures out how to plug it. History OR&R’s expertise stems strictly from experience. They analyze and recommend responses based on what they’ve seen with hundreds of previous spills. Much of that experience has been in the Gulf of Mexico, which sits atop massive oil deposits. Millions of gallons per year seep naturally into the gulf, and hardly a week passes without something spilling there. Tankers collide or run aground. Aging pipelines fail. Oil platforms spring leaks. North America’s largest had been the Mexican Ixtoc platform, which blew out in 1979 and spewed up to 300 million gallons into gulf waters over the span of nine months. Two months later, oil began to wash up on Texas beaches. It was an unholy mess, but the environment seemed to recover within a year or two. But the Ixtoc spill occurred in about 200 feet of water. BP’s spill is something else again. Depth NOAA scientists have no experience with a spill 5,000 feet beneath the surface. The water at that depth is about 40 degrees Fahrenheit, which is colder than Alaskan waters. Oil being less dense than water, the stuff immediately goes to the surface, but they don’t know what happens on the way up. And they don’t know how to accurately measure how much oil is leaking. “We’ve had some experience with oil from sunken vessels at the depth,” Helton says. “But that oil is in smaller quantities and it isn’t under pressure.” NOAA stores vast amounts of data on marine life along US shores, but scientists know relatively little about what lives a mile beneath the surface, let alone how deepsea organisms react to oil. A year or two from now, they’ll know more, having learned the hard way. Dispersants Early on, OR&R recommended injecting chemical dispersants at the pipe. Scientists believe the chemicals are helping break huge plumes down into smaller drops that will evaporate or disperse more quickly. But reporters and environmentalists wondered if pouring more chemicals into the sea wouldn’t just exacerbate the problem. It’s a tradeoff, Helton says. The chemistry of dispersants is similar to dish detergent, he says. “It spreads more oil at the surface.” But the questions keep coming. Boom State and local officials demand to know why the government hasn’t installed oil booms along gulf shores to protect beaches. But NOAA’s experience suggests that oil boom has limited uses, and you can’t protect an entire seashore–especially when you don’t know where or when the oil is going to come ashore. “You don’t want to shoot all your ammunition in the first few minutes of the battle,” one scientist explains. Once deployed, oil boom has a limited lifetime. Battered by waves and currents, plastic booms soon lose their effectiveness. So the trick is to have it available to protect specific shorelines as the slick approaches. That strategy is not terribly comforting to gulf fishermen and others frustrated that nothing seems to be happening to protect their fishing grounds and beaches. Which way did it go? Whatever the size of the spill, it has taken its sweet time finding its way to Gulf beaches. In part, this may be because chemical dispersants are working as hoped–breaking the slick up into smaller particles that mix quickly with seawater or evaporate at the surface. Scientists also believe that the spring outflow from the Mississippi River has washed much of the oil away from Louisiana shores. The good news is that NOAA and other officials gain ed valuable time to prepare. The bad news is that hundreds of TV camera crews and reporters who converged on the scene, expecting to get film of oiled beaches, soon ran out of news to report. Questions about chemical dispersants and the exact volume of the spill became a national story. Another wave of reports suggested a huge underwater plume of oil, 10 miles long, moving toward Florida. If this is the case, the NOAA scientists explain, “you’d have to suspend the laws of physics.” Oil is lighter than water, so goes immediately to the surface. But the story persists. And so it goes. Helton and his colleagues are hunkered down for the long haul. The “media spill” will wane and the politics will shift somewhere else. But the oil will keep gushing out of that hole in the bottom of the ocean. Image Credit: NASA Earth Observatory. Sunlight illuminated the lingering oil slick off the Mississippi Delta on May 24, 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this image the same day. Oil smoothes the ocean surface, making the Sun’s reflection brighter in some places, and reducing the scattering of sunlight in other places. As a result, the oil slick is brighter than the surrounding water in some places (image center) and darker than the surrounding water in others (image lower right). The tip of the Mississippi Delta is surrounded by muddy water that appears light tan. Bright white ribbons of oil streak across this sediment-laden water. Tendrils of oil extend to the north and east of the main body of the slick. A small, dark plume along the edge of the slick, not far from the original location of the Deepwater Horizon rig, indicates a possible controlled burn of oil on the ocean surface. To the west of the bird’s-foot part of the delta, dark patches in the water may also be oil, but detecting a manmade oil slick in coastal areas can be even more complicated than detecting it in the open ocean.