Remotely operated vehicles (ROV) investigating a recurring sheen near the deepwater Macondo wellhead and Deepwater Horizon semisubmersible wreckage identified no sources of leaking oil, officials said.
BP PLC operated the Macondo well, which was drilled by Transocean Ltd. using the Deepwater Horizon. An April 2010 blowout resulted in the deaths of 11 people aboard the Deepwater Horizon, which sank after a fire and explosion. The blowout caused a massive oil spill.
The latest ROV inspection, which concluded Dec. 16, was prompted by a report that a sheen was observed during November. An unidentified substance inconsistent with oil was seen emitting from several areas of the rig wreckage, and samples were collected for further lab analysis.
“No apparent source of the surface sheen has been discovered by this effort,” said US Coast Guard Capt. Duke Walker, federal on-scene coordinator. “Next steps are being considered as we await the lab results of the surface and subsurface samples and more detailed analysis of the video shot during the mission."
The Macondo wellhead was found to be secure. On Sept. 19, 2010, the well was closed off and cemented.
Satellite surveillance will continue to monitor the sheen while future steps are being considered.
The real time ROV operations were observed remotely by government officials. Video of the ROV inspections will be made available shortly and posted online.
In September BP reported a sheen and discovered a containment dome was leaking oil. An ROV operation was done to cap the containment dome leaks. No oil emissions from the containment dome were observed after the capping operation (OGJ Online, Nov. 30, 2012).