Shell reports sheen in central Gulf

Federal officials are investigating a reported light sheen spanning a 10-mile area in the central Gulf of Mexico.

Shell Oil reported the light sheen to the government’s National Response Center on Wednesday, but said in a statement that the company had “no current indication” that it originates from the firm’s nearby wells. The source of the rainbow sheen is unclear. It also is not clear whether the sheen is caused by oil or another substance.

The sheen is located between two existing oil production sites — the Mars and Ursa projects — about 130 miles southeast of New Orleans. Shell operates both projects, but BP has a working interest in the Mars field. BP, Exxon Mobil Corp., and ConocoPhillips each have working interests in the Ursa project.

Several oil companies also work in the surrounding waters, which are in the same federal leasing area as the failed BP Macondo well that launched the nation’s worst oil spill when it blew out almost two years ago. That area, known as Mississippi Canyon, includes active projects in widely ranging water depths up to at least 7,300 feet.

Shell said in its statement that it has mobilized an oil spill skimming ship — the Marine Spill Response Corp.’s Louisiana Responder –  “out of prudent caution.” That skimming vessel is expected to be on the site by Thursday morning, said Coast Guard Petty Officer 2nd Class Bill Colclough.

“Shell also has requested flights to monitor the one by 10-mile sheen closely with additional aerial surveillance,” said company spokeswoman Kelly op de Weegh. “At this time, the source of this sheen is unknown, and Shell’s priority is to respond proactively, safely, and in close coordination with regulatory agencies.”

The Interior Department’s Bureau of Safety and Environmental Enforcement said in a statement that the agency was “taking steps to identify the source of (the) sheen . . . and will continue to coordinate with the U.S. Coast Guard to respond to and monitor any potential pollution.”

Colclough said Coast Guard officials out of the Morgan City Marine Safety Unit are investigating the report. A Coast Guard air crew based in New Orleans is set to fly over the site at first light Thursday to assess the sheen.