Deepwater Horizon Well Leaking Oil
Scientists: Oil fouling Gulf matches Deepwater Horizon well
By Ben Raines
MOBILE, Alabama — Scientific analysis has confirmed that oil bubbling up above BP’s sealed Deepwater Horizon well in recent days is a chemical match for the hundreds of millions of gallons of oil that spewed into the Gulf last summer.
The Press-Register collected samples of the oil about a mile from the well site on Tuesday and provided them to Ed Overton and Scott Miles, chemists with Louisiana State University.
The pair did much of the chemical work used by federal officials to fingerprint the BP oil, known as MC252.
“After examining the data, I think it’s a dead ringer for the MC252 oil, as good a match as I’ve seen,” Overton wrote in an email to the newspaper. “My guess is that it is probably coming from the broken riser pipe or sunken platform. … However, it should be confirmed, just to make sure there is no leak from the plugged well.”
In an emailed statement, BP officials wrote that the company had a vessel stationed at the site all day Thursday but never saw any oil.
During BP’s inspection, the wind was blowing up to 10 mph, and waves were up to 2 feet high. Scientists said that even a light chop would likely have obscured the small sheens emerging every few seconds.
By contrast, the wind was still and seas were flat and glassy Tuesday when the newspaper located the oil.
“There is still no evidence that the oil came from the Macondo well,” BP officials wrote in the emailed statement.
Late Thursday night, BP officials sent word that an ROV survey of the well found no leaks.
It took several hours for the Press-Register to locate the small area where oil was bubbling to the surface. Scientists said the location where oil emerged would change continually, depending on water currents.
In response to a Press-Register story about the find, the U.S. Coast Guard sent a helicopter and a boat to the well site Thursday but failed to find any oil, according to Capt. Jonathon Burton, who oversees operations in that portion of the Gulf.
“If it is a natural seepage, or a burp out of the wreckage down below, that would explain why we had something two days ago and not today,” Burton said.
He said knowing that the oil matches with the BP well was useful, as it ruled out the possibility of other sources, such as the pipelines that crisscross the Gulf floor.
“The good news is it looks as if we’ve ruled out any significant source,” Burton said, referring to the apparently small amount of oil hitting the surface. “We certainly need to see if we can pinpoint the cause. We’re going to work that way.”
Burton speculated that wind and sea conditions might have played a role in hiding the oil during the Coast Guard inspections.
“The next time we’ve got a nice flat calm day, we’re coordinating to get something out there to see what might be coming up at that point,” Burton said.
Bonny Shumaker, a pilot with On Wings of Care, along with members of the Gulf Restoration Network, first observed the oil sheens from the air on Friday and reported the location as the Macondo well site.
During the newspaper’s Tuesday trip, the area where oil sheens could be seen blooming on the surface regularly was about an acre in size. The oil was the heaviest about a mile from the well.
Robert Bea, a prominent University of California petroleum engineer studying the BP spill, was not surprised that oil was seen away from the well head. Bea said he believed there was a high probability that the oil originated from the BP well.
“Looks suspicious. The point of surfacing about one mile from the well is about the point that the oil should show up, given the seafloor at 5,000 feet … natural circulation currents would cause the drift,” Bea said. “A remote operated vehicle (ROV) could be used to ‘back track’ the oil that is rising to the surface to determine the source. This should be a first order of business to confirm the source.”
Bea provided drawings to the newspaper that illustrated how oil might be able to rise up from thousands of feet underground along the outside of the sealed well pipe.
“Perhaps connections that developed between the well annulus (outside the casing), the reservoir sands about 17,000 feet below the seafloor and the natural seep fault features” could provide a pathway for oil to move from deep underground to the seafloor.
Philip Johnson, author of the Standard Handbook of Petroleum and Natural Gas Engineering and a professor at the University of Alabama, suggested that trapped oil might be escaping from the wreckage of the Deepwater Horizon drilling rig, which is still sitting on the seafloor.
Other possibilities, he said, included heavy oil deposited on the seafloor slowly being degraded by bacteria and releasing lighter components, a natural seep, or, in a worst case scenario, a leak in the 5,000 foot long cement plug used to seal the well.
Outdoors Editor Jeff Dute contributed to this report.