HUNTINGTON BEACH, California — An oil sheen spotted off the coast of Southern California last week may have been caused by natural seepage from the ocean floor, but the exact source is still unknown, U.S. Coast Guard officials said Monday.
Authorities discovered the 2.5-mile-long (4-kilometer-long) oil sheen off the coast of Huntington Beach on Friday morning. Crews recovered about 322 gallons of oil from the water and 476 pounds of oily waste and tar balls from the shoreline, the Coast Guard said in a statement.
Laboratory tests so far have not definitively identified the oil source, but preliminary analyzes indicated it was not a refined product like gasoline or diesel, officials said.
“The laboratory results were also inconsistent with archived samples from oil platforms in the area,” the statement said. The samples, officials say, are more indicative of “freshly produced” oil typical of natural seeps.
Authorities initially said there were no reports of spills or spills from oil platforms operating offshore and that the sheen did not appear to be growing, leading them to suspect it was a one-time spill of oil from the ocean floor, which is quite common. .
By the time rescuers conducted flights over the area on Saturday, they could no longer see any recoverable sheen. There were some tar lumps along the beach, but not enough to warrant a weekend closure, and there did not appear to be any threat to public health, officials said.
The Coast Guard said three live birds – a cormorant, a duiker and a grebe – were oiled and treated.
A 2021 offshore pipeline leak caused globs of crude oil to wash up in Huntington Beach, a surf-friendly city about 30 miles (48 kilometers) southeast of Los Angeles.
