On Thursday, the New York Times said that the size of the Gulf Disaster oil leak is being underestimated, two weeks after we did. -- On Apr. 29 we wrote: "Media are continuing to fail to question the estimates of oil pouring into the Gulf, though any bright ten-year-old would be able to deduce that the estimates being made (1,000 barrels a day, raised Wednesday to 5,000 barrels a day) are most likely vague numbers pulled out of the air -- or in this case, the water." -- A BP senior vice president recently said that "There’s just no way to measure it,” but in fact, it turns out, "for decades, specialists have used a technique that is almost tailor-made for the problem. With undersea gear that resembles the ultrasound machines in medical offices, they measure the flow rate from hot-water vents on the ocean floor. Scientists said that such equipment could be tuned to allow for accurate measurement of oil and gas flowing from the well."[1] -- But the Times didn't say what CNN reported early Friday: that "a researcher at Purdue University has predicted that about 70,000 barrels of oil per day are gushing into the Gulf after analyzing videos of the spill. -- Associate professor Steve Wereley said he arrived at that number after spending two hours Thursday analyzing video of a spill using a technique called particle image velocimetry. He said there is a 20 percent margin of error, which means between 56,000 and 84,000 barrels could be leaking daily."[2] ...
1.
U.S.
SIZE OF OIL SPILL UNDERESTIMATED, SCIENTISTS SAY
By Justin Gillis
New York Times
May 13, 2010
http://www.nytimes.com/2010/05/14/us/14oil.html
Two weeks ago, the government put out a round estimate of the size of the oil leak in the Gulf of Mexico: 5,000 barrels a day. Repeated endlessly in news reports, it has become conventional wisdom.
But scientists and environmental groups are raising sharp questions about that estimate, declaring that the leak must be far larger. They also criticize BP for refusing to use well-known scientific techniques that would give a more precise figure.
The criticism escalated on Thursday, a day after the release of a video that showed a huge black plume of oil gushing from the broken well at a seemingly high rate. BP has repeatedly claimed that measuring the plume would be impossible.
The figure of 5,000 barrels a day was hastily produced by government scientists in Seattle. It appears to have been calculated using a method that is specifically not recommended for major oil spills.
Ian R. MacDonald, an oceanographer at Florida State University who is an expert in the analysis of oil slicks, said he had made his own rough calculations using satellite imagery. They suggested that the leak could “easily be four or five times” the government estimate, he said.
“The government has a responsibility to get good numbers,” Dr. MacDonald said. “If it’s beyond their technical capability, the whole world is ready to help them.”
Scientists said that the size of the spill was directly related to the amount of damage it would do in the ocean and onshore, and that calculating it accurately was important for that reason.
BP has repeatedly said that its highest priority is stopping the leak, not measuring it. “There’s just no way to measure it,” Kent Wells, a BP senior vice president, said in a recent briefing.
Yet for decades, specialists have used a technique that is almost tailor-made for the problem. With undersea gear that resembles the ultrasound machines in medical offices, they measure the flow rate from hot-water vents on the ocean floor. Scientists said that such equipment could be tuned to allow for accurate measurement of oil and gas flowing from the well.
Richard Camilli and Andy Bowen, of the Woods Hole Oceanographic Institution in Massachusetts, who have routinely made such measurements, spoke extensively to BP last week, Mr. Bowen said. They were poised to fly to the gulf to conduct volume measurements.
But they were contacted late in the week and told not to come, at around the time BP decided to lower a large metal container to try to capture the leak. That maneuver failed. They have not been invited again.
“The government and BP are calling the shots, so I will have to respect their judgment,” Dr. Camilli said.
BP did not respond Thursday to a question about why Dr. Camilli and Mr. Bowen were told to stand down. Speaking more broadly about the company’s policy on measuring the leak, a spokesman, David H. Nicholas, said in an e-mail message that “the estimated rate of flow would not affect either the direction or scale of our response, which is the largest in history.”
Dr. MacDonald and other scientists said the government agency that monitors the oceans, the National Oceanic and Atmospheric Administration, had been slow to mount the research effort needed to analyze the leak and assess its effects. Sylvia Earle, a former chief scientist at NOAA and perhaps the country’s best-known oceanographer, said that she, too, was concerned by the pace of the scientific response.
But Jane Lubchenco, the NOAA administrator, said in an interview on Thursday: “Our response has been instantaneous and sustained. We would like to have more assets. We would like to be doing more. We are throwing everything at it that we physically can.”
The issue of how fast the well is leaking has been murky from the beginning. For several days after the April 20 explosion of the Deepwater Horizon rig, the government and BP claimed that the well on the ocean floor was leaking about 1,000 barrels a day. [Actually, at first officials said there was no leak at all. (http://www.ufppc.org/us-a-world-news-mainmenu-35/9551/)]
A small organization called SkyTruth, which uses satellite images to monitor environmental problems, published an estimate on April 27 suggesting that the flow rate had to be at least 5,000 barrels a day, and probably several times that.
The following day, the government -- over public objections from BP -- raised its estimate to 5,000 barrels a day. A barrel is 42 gallons, so the estimate works out to 210,000 gallons per day.
BP later acknowledged to Congress that the worst case, if the leak accelerated, would be 60,000 barrels a day, a flow rate that would dump a plume the size of the Exxon Valdez spill into the gulf every four days. BP’s chief executive, Tony Hayward, has estimated that the reservoir tapped by the out-of-control well holds at least 50 million barrels of oil.
The 5,000-barrel-a-day estimate was produced in Seattle by a NOAA unit that responds to oil spills. It was calculated with a protocol known as the Bonn convention that calls for measuring the extent of an oil spill, using its color to judge the thickness of oil atop the water, and then multiplying.
However, Alun Lewis, a British oil-spill consultant who is an authority on the Bonn convention, said the method was specifically not recommended for analyzing large spills like the one in the Gulf of Mexico, since the thickness was too difficult to judge in such a case.
Even when used for smaller spills, he said, correct application of the technique would never produce a single point estimate, like the government’s figure of 5,000 barrels a day, but rather a range that would likely be quite wide.
NOAA declined to supply detailed information on the mathematics behind the estimate, nor would it address the points raised by Mr. Lewis.
Mr. Lewis cited a video of the gushing oil pipe that was released on Wednesday. He noted that the government’s estimate would equate to a flow rate of about 146 gallons a minute. (A garden hose flows at about 10 gallons per minute.)
“Just anybody looking at that video would probably come to the conclusion that there’s more,” Mr. Lewis said.
The government has made no attempt to update its estimate since releasing it on April 28.
“I think the estimate at the time was, and remains, a reasonable estimate,” said Dr. Lubchenco, the NOAA administrator. “Having greater precision about the flow rate would not really help in any way. We would be doing the same things.”
Environmental groups contend, however, that the flow rate is a vital question. Since this accident has shattered the illusion that deep-sea oil drilling is immune to spills, they said, this one is likely to become the touchstone in planning a future response.
“If we are systematically underestimating the rate that’s being spilled, and we design a response capability based on that underestimate, then the next time we have an event of this magnitude, we are doomed to fail again,” said John Amos, the president of SkyTruth. “So it’s really important to get this number right.”
This article has been revised to reflect the following correction:
Correction: May 13, 2010
An earlier version of this article misstated the date of the explosion on the Deepwater Horizon rig.
2.
U.S.
CONGRESSMAN TO LAUNCH INQUIRY ON HOW MUCH OIL IS GUSHING INTO GULF
CNN
May 14, 2010
http://www.cnn.com/2010/US/05/14/gulf.oil.spill/
A U.S. congressman said he will launch a formal inquiry Friday into how much oil is gushing into the Gulf of Mexico after learning of independent estimates that are significantly higher than the amount BP officials have provided.
Rep. Edward Markey, a Democrat from Massachusetts, said he will send a letter to BP and ask for more details from federal agencies about the methods they are using to analyze the oil leak. Markey, who chairs a congressional subcommittee on energy and the environment, said miscalculating the spill's volume may be hampering efforts to stop it.
"I am concerned that an underestimation of the oil spill's flow may be impeding the ability to solve the leak and handle the management of the disaster," he said in a statement Thursday. "If you don't understand the scope of the problem, the capacity to find the answer is severely compromised."
BP officials have said 5,000 barrels per day of crude, or 210,000 gallons, have been leaking for the past three weeks.
But a researcher at Purdue University has predicted that about 70,000 barrels of oil per day are gushing into the Gulf after analyzing videos of the spill.
Associate professor Steve Wereley said he arrived at that number after spending two hours Thursday analyzing video of a spill using a technique called particle image velocimetry. He said there is a 20 percent margin of error, which means between 56,000 and 84,000 barrels could be leaking daily.
"You can't say with precision, but you can see there's definitely more coming out of that pipe than people thought. It's definitely not 5,000 barrels a day," Wereley said.
He said he reached his estimate of 70,000 barrels per day by calculating how far and how fast oil particles were moving in the video.
Markey's statement said that officials from BP, Transocean and Halliburton estimated a worst-case-scenario maximum flow at 60,000 barrels a day during congressional testimony Tuesday.
More than 260,000 barrels of oil spilled during the 1989 wreck of the supertanker Exxon Valdez in Alaska's Prince William Sound.
BP spokesman Mark Proegler said that the company stands by its 5,000 barrels per day estimate. He said the company reached that number using data, satellite images, and consultation with the Coast Guard and the National Oceanic and Atmospheric Administration. But there is no way to calculate a definite amount, he said.
"We are focused on stopping the leak and not measuring it," he said.
Oil has been gushing into the gulf since April, when an explosion sank the Deepwater Horizon drill rig. The blast left 11 workers lost at sea.
BP said Thursday that it would attempt to insert a new section of pipe into the riser of its damaged undersea well to capture the leaking oil.
A previous effort to cap the gusher with a four-story containment dome failed when natural gas crystals collected inside the structure, plugging an outlet at the top.
BP, the Coast Guard, and state and local authorities have scrambled to keep the oil from reaching shore or the ecologically delicate coastal wetlands off Louisiana. They have burned off patches of the slick, deployed more than 280 miles of protective booms, skimmed as much as 4 million gallons of oily water off the surface of the Gulf and pumped more than 400,000 gallons of chemical dispersants onto the oil.
Investigators are still trying to determine what caused the April 20 explosion aboard the Deepwater Horizon.
BP has blamed drilling contractor Transocean Ltd., which owned the rig. Transocean says BP was responsible for the wellhead's design and that oilfield services contractor Halliburton was responsible for cementing the well shut once drilled. And Halliburton says its workers were just following BP's orders, but that Transocean was responsible for maintaining the rig's blowout preventer.
--CNN's Ed Lavandera contributed to this report.
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