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Advanced ocean science tech helps researchers study the spill

The night of June 21, 2010, Reddy and colleagues from the Woods Hole Oceanographic Institution were whisked off their research vessel Endeavor to collect samples directly from the blown Macondo well, which had been spewing oil and natural gas into the Gulf of Mexico for two months. They had 12 hours to do something that had never been done before: Use a robot arm to stick a special bottle directly into the hot hydrocarbons. Now, a year later, their analysis explains just what came out of the well, and sheds more light on what happened to it.

It turns out that certain chemicals in the well behave differently under high pressure than they do at the surface. This explains why some chemicals, but not others, made their way into the huge 22-mile plume of oil that Reddy et. al uncovered last summer. It also explains why some scientific papers examining the spill have seemed to contradict each other, according to Don Rice, director of the National Science Foundation’s chemical oceanography program.

“We now have a far better understanding of how and why an oil ‘spill’ into the ocean from below differs from one from above. The significance of this work extends well beyond the Gulf of Mexico,” he said in a statement.

One of the most confounding problems with the oil spill was scientific uncertainty — about how much oil was leaking into the Gulf, and about what exactly it was, both of which would explain where the oil would go. Reddy and colleagues needed to go directly to the source — the gusher at 5,000 feet below the surface — to see the compounds and therefore understand what would happen to the plume. This sample is called an “end member,” Reddy explained in an interview. A significant fraction of the gusher consisted of hot gas, mainly methane, so this proved a difficult task.

“If you tried to lower a traditional tool into that boiling cauldron and then close it and bring it up to the surface, that bottle would explode. A tiny methane bubble at 5,000 feet becomes a giant methane bubble at atmospheric pressure,” Reddy said.

The research team turned to Woods Hole geochemist Jeff Seewald, who developed a tool called an isobaric gas-tight sampler. It’s intended for collecting fluids from deep-sea hydrothermal vents. They used an oil industry ROV to place the IGT sampler directly over the broken riser pipe, and they collected the only undiluted, non-degraded sample from the spill.

The team found a gas-to-oil ratio of 1,600 cubic feet of gas per barrel of oil, according to a paper on the findings published this week in the Proceedings of the National Academy of Sciences and funded by the NSF. Based on this ratio, and using the federal government’s estimate of 4.1 million barrels of oil, Reddy et. al estimate 1.7 × 1011 g of methane, ethane and propane leaked into the Gulf. That’s about 105 tons. That’s a lot of methane.

But perhaps more interesting is the makeup of the plume, which mostly comprised benzene, toluene, ethybenzene, and total xylenes, or BTEX. BTEX compounds only represented about 2 percent of the oil that came out of the well, but almost 100 percent of the deep-sea plume. They apparently took a right-hand turn 3,000 feet below sea level, whereas the other hydrocarbons — like methane — degraded, washed on shore, were eaten by bacteria, or were burned in the fires that Reddy experienced while gathering his sample.

Studying the plume also required a bit of technical wizardry, Reddy said. WHOI researcher Richard Camilli built a super-sensitive mass spectrometer, which can instantly identify minute quantities of petroleum and other chemical compounds. This tool was used in the initial plume studies last summer, and it helped researchers quantify how the plume and the wellhead gusher were different.

“It shows some of these compounds are likely to evaporate quicker, at shallower depths. Oil is made up of many compounds, and they all have different chemical and physical properties. This work highlights that. Those properties determine what chemicals went into the plume,” Reddy said.

On the surface, this is all different — BTEX compounds quickly volatilize and evaporate into the atmosphere.

“In the case of the Deepwater Horizon oil spill, however, gas and oil experienced a significant residence time in the water column with no opportunity for the release of volatile species to the atmosphere,” the researchers write in the PNAS paper. “Hence, water-soluble petroleum compounds dissolved into the water column to a much greater extent than is typically observed for surface spills.”

The good news is that BTEX is not toxic to marine organisms until it reaches much higher levels than the researchers found in the Gulf. But neurological impairments can occur at lower concentrations, according to the National Science Foundation. It remains to be seen how the persistent BTEX may have affected sea life.

Meanwhile, Reddy and his colleages are still collecting samples from the beaches lining the Gulf Coast. He praised the National Science Foundation for funding ongoing oil spill research programs, which proved useful in the Deepwater Horizon crisis.

“We will continue to hunt and look for remnants of this oil for as long as we can be funded,” he said. “There’s a lot to be learned, about what compounds resist degradation from nature. It sheds tremendous light on this field.”

Within four months of the oil spill, bacterial blooms had removed more than 200,000 metric tons of dissolved methane, returning concentrations to normal background levels.

That was a surprise, because in mid-June, scientists found methane concentrations nearly 100,000 times above normal levels, and learned it was decomposing slowly, suggesting it would take years for the hydrocarbon to dissipate.

“We couldn’t have been more wrong. It decomposed rather quickly and was completely consumed within a matter of months,” said lead researcher John Kessler, an oceanographer at Texas A&M University, in a news release.

Kessler and colleagues took three cruises aboard the NOAA ship Pisces between Aug. 18 and Oct. 4, collecting 207 separate water samples and measuring their oxygen and methane concentrations. Oxygen drops when bacteria breathe methane, so the researchers say the depleted oxygen levels can only be explained by consumption of the methane.

They also examined the genetic sequences of bacteria in the samples, which suggested a growing population of methane-munching life forms.

Methane, the primary ingredient in natural gas, was to blame for the spill in the first place — on April 20, a methane bubble surged from the Macondo well up the Deepwater Horizon’s drill column, busting several seals as it belched toward the rig. The resulting explosion killed 11 workers and severed the rig from the well, allowing oil to spew forth for 83 days.

As workers attempted to burn, vacuum, sponge and contain the oil, invisible microbial communities were hard at work. Scientists said last August that a previously undiscovered species of bacteria had made quick work of a massive oil plume; apparently methanotrophs, species of methane-munching bacteria, were also feasting on the spill.

Bacteria have evolved to live with the Gulf’s naturally occurring oil seeps and high methane concentrations, so it makes sense that they were ready to go to work. Apparently they are more effective than we thought.

As with any controversial study, not everyone was satisfied with the results — Ian MacDonald, a professor of biological oceanography at Florida State University, told NPR the team did not account for deep-sea currents that could have carried away the methane. Further studies will shed more light on the findings.

[Science]

Samantha Joye, a professor in the Department of Marine Sciences at the University of Georgia, set sail August 21 on the research vessel Oceanus and has been posting blog updates throughout the mission. Over the weekend, she wrote that her team found a layer of oil in a valley on the seafloor, about 18 miles from the wellhead. It is two inches thick in some spots, and it rests on top of recently dead sea creatures like shrimp and tubeworms.

Joye expected to find some oil on the seafloor, she told the AP — just not that much. Her team is the second in as many months to announce finding oil at the bottom; last month, a University of South Florida crew reported finding oil droplets 1.4 miles beneath the surface.

The presence of seafloor oil is another blow to the theory that most of the spilled oil disappeared. Scientists previously said plenty of oil was floating in an invisible plume, and while yet another research team said microbes were eating it, not all of it could be accounted for. Several experts, including some government scientists, believe at least some of the oil sank to the bottom, and that’s what Joye’s research seems to prove.

Although she can’t be certain until they conduct further tests this week, the oil almost certainly came from the spill and not a natural seep, Joye said. It clearly came from above the seafloor, not below, she says in her blog post.

The oil layer is pretty dispersed, indicating that chemical dispersants broke it down into small droplets. In an interview with NPR, she also reported finding small tar balls that look like cauliflower heads. While dispersants likely helped some of the oil sink to the bottom, Joye said natural processes also played a role. As microorganisms break down oil, they excrete mucus, which eventually sinks to the bottom.

Government scientists acknowledge they have not done a good enough job looking for oil at the bottom of the sea. It’s partly because the environment is so difficult — teams have to use send 1,000-pound vessels to the seafloor where they can pull up core samples. The AP quoted a NOAA official saying government and BP vessels will plumb the depths in the coming weeks.

[AP]

Burtynysky has long been known for his work documenting the impact of the oil industry on natural landscapes. His photography has brought him around the world, shooting pipelines in Canada, oilfields in Azerbaijan, and major highways in Los Angeles.

When the Gulf Coast oil spill first started making headlines, it seemed only appropriate for Burtynysky to photograph it. After all, it is his ability to show magnitude in his images (which are themselves printed large), that makes his work so breathtaking and relevant. His images of the oil spill are no exception, providing an eerie look into something too massive and destructive to truly comprehend.

Eight of these photographs will be on display at the Nicholas Metivier Gallery located in Toronto Canada from September 16 to October 9.

[Metivier Gallery via Gizmodo]

This is a cross-post from PopPhoto.com

The belt is made of an ultra-light nanowire mesh, patented at MIT, that can absorb up to 20 times its weight in oil. Its hydrophobic properties deflect water while sucking up various forms of pollution. The nanowire's inventors have compared it to a paper towel for oil spills.

The belt attaches to a yellow “head” covered in photovoltaic panels, according to its designers, based at MIT’s Senseable City Lab. As the robot moves head-first through the water, the conveyor belt sucks up oil, which is squeezed out into the head. As the clean part of the belt emerges from the head, the process starts over.

Seaswarm robots are intended to work as a fleet, hence the name. The robots would communicate via GPS and WiFi networks to coordinate clean-up, and they would not require human involvement, unlike current ocean skimmers. They are just 16 feet long by seven feet wide, so they would be able to access coastlines, marshes and estuaries, unlike current skimmers that attach to boats.

The design team tested their prototype in Boston’s Charles River this month and they say the conveyor belt easily adapted to the surface waves.

The robot works by detecting the edge of a spill and moving inward until it has removed the oil, the project's Web site says. Because the robot's head consumes the oil, the robot does not need to make repeated trips back to shore, making it a much more efficient cleaner.

The massive plume scientists announced last week might already be gone

“In the last three weeks, we haven’t been able to detect the deepwater plume anywhere we’ve gone,” he said in an interview. “It appears to have been completely biodegraded and diluted out. Like the surface (oil), we can no longer find it.”

Remember how we also told you about the added variable of politics and money? This finding was partly funded by research dollars from BP. The funds were from an existing 10-year BP grant and have nothing to do with the oil spill, though.

Hazen, with Berkeley Lab’s earth sciences division, said the bacteria are adapted to break down oil at very cold temperatures, which was somewhat surprising. It’s the first time anyone has ever studied microbial degradation at such depths.

The bacteria also appear to do this without a lot of oxygen, which is more good news for those concerned about oxygen-free “dead zones” in the water column. Hazen and more than 30 colleagues report on their findings in a paper published today in the online edition of the journal Science.

Last week, Richard Camilli et. al announced the discovery of a massive oil plume, but said they could not yet tell how dense it was, how much of the spilled oil was in it, and other variables. Using oxygen concentrations as a proxy for bacterial degradation — bacteria consume oxygen — they also estimated that bacteria were not breaking down the oil very quickly.

Hazen’s study says not only are bacteria gobbling up the oil, they’ve gobbled up so much that researchers can’t find the plume anymore.

His data comes from more than 200 samples collected between May 25 and June 2, from a plume of oil that extended at least 10 miles past the wellhead (the same plume Camilli et. al announced last week). The Berkeley Lab team used a DNA microchip to study the genes of the bacteria inside the oil plume, and they found a wide variety of hydrocarbon degraders. The chip helped the team identify the new species.

Hazen has spent three decades studying microbial degradation of hydrocarbons. He said he agreed with federal estimates from earlier this month that much of the oil had been degraded, adding that doubters have not been in the field as recently as he: “Most of us that work in this field expected it,” he said. “The ones that didn’t accept it were the ones that hadn’t been out there in the field recently. All of us that have been out there ... and are monitoring it, accept that.”

Ron Kendall, chair of the department of environmental toxicology at Texas Tech and director of the university’s Institute for Environmental and Human Health, said the study confirms that at least one huge oil plume exists, and that bacteria are helping to break it down. But no one has yet confirmed Hazen's findings, which center partly on the faster-than-expected oil biodegradation rates.

"There’s a lot of science that needs to be done. These are just some of the beginning pieces of evidence that, No. 1, plumes exist; No. 2, microbes do exist that can eat the oil in a plume; and No. 3, the (hydrocarbon) half-life phenomena is open to debate," he said. "I just think that we need to continue to look, and if there’s one plume, there’s probably others. We just can’t find them."

About that BP funding: In a news release, Berkeley Lab was quick to disclose this, although it has nothing to do with the oil spill. After a competition three years ago, BP awarded a $500 million, 10-year grant to a group of institutions, led by the University of California-Berkeley, to create an Energy Biosciences Institute. The oil giant was interested in obtaining ethanol from cellulose, as well as other research. Last year, BP added about $2 million a year for Hazen’s group to study enhanced hydrocarbon recovery, which includes using marine microorganisms to increase the viscosity of oil inside land-based wells, among other research areas. Hazen said he does not have any restrictions on publishing his work.

“That’s one of the reasons we were able to go out into the field immediately and start working on this. We had already set up whole teams to do these types of things for oil,” Hazen said. “There are no restrictions on us whatsoever in terms of what we’re seeing, in terms of anything that we do. We are a (U.S. Department of Energy) national laboratory and those things wouldn’t be allowed.”

So what does this mean?

For one, we finally have data that explains what happens to the microbial community when oil is released into the deep sea. Organisms that evolved to feed on natural oil-seeps will spring into action, reproducing at exponential rates. Hazen said tracking these organisms could be a new method to find oil hidden in the depths. And at the very least, it’s good news for future oil spill remediation — these microbes are awfully good at breaking down oil.

We also know that this has been happening all along, perhaps from the day the Deepwater Horizon rig exploded. Hazen said widespread use of dispersant may have even sped up the process by breaking the oil into snack-sized microdroplets, making the bacteria’s task easier.

But while the bacteria brings good news, the saga is still far from over. There’s still oil in the ocean, Hazen said, and some hydrocarbon elements can be toxic even at the most dilute concentrations. The fact that bacteria are eating it does not necessarily signal an “all clear” — especially not for the zooplankton, phytoplankton and other marine life that lived with the oil for three months.

When he announced the initial oil plume study last week, Woods Hole marine geochemist Chris Reddy said patience is key: “We all want data in 8 seconds, and that’s just not going to happen in this world. We will know more with time, as more data comes out of the pipeline.”

Kendall said there's still plenty of it coming.

"Just think about how few days have been spent on the water trying to get this information, versus the scope of the area," he said.

As of today, Wednesday, June 9, the oil spewing from the Deepwater Horizon well could have powered 38,000 cars, 3,400 trucks and 1,800 ships for a full year, according to University of Delaware professor James J. Corbett.

Corbett, a marine policy professor, has a Web site that calculates the spilled oil's lost potential on a daily basis. He uses an estimate of 19,000 barrels a day, the most recent government guess. He says he created the site to put the spill in perspective that petroleum users can easily understand.

Meanwhile, Science Magazine estimates $1 million in oil is being spilled each day.

And that's saying nothing of the lingering economic effects.

[PhysOrg]