BP: ‘Cofferdam’ is ‘Probable Source’

After three days of inspecting the Macondo well, BP has announced that the current oil sheen in the Gulf of Mexico is likely due to the ‘cofferdam’—a 86-ton dome used in one of the company’s failed containment attempts.

“The latest survey marks the third time since the Macondo well was permanently sealed in September of 2010 that it has been visually inspected at the sea floor and confirmed not to be leaking,” read a BP statement released yesterday.

For more than a month, a surface sheen has been visible at the site of the 2010 Deepwater Horizon disaster. After positively fingerprinting the surface oil to Macondo, the U.S. Coast Guard instructed BP to determine where the oil was coming from. The company has pointed to the ‘cofferdam’ as the “probable source of the surface sheen.”

“The cofferdam is a 86-ton, steel container that was lowered over a leaking drill pipe at the Macondo well site in May 2010 in an attempt to capture the oil and funnel it to the surface,” the BP statement read. “A mixture of oil and slushy methane hydrates was trapped inside the cofferdam during the response.”

On Oct. 17, a remotely operated vehicle (ROV) videoed “small, intermittent drops of oil coming from an opening at the top and another on one side of the cofferdam.” Samples of the oil escaping from the equipment were collected, and will be compared to the surface sheen to confirm a match.