What caused a 2-mile long oil sheen spotted offshore of Huntington Beach late last week is still unclear, but enough has been cleaned up for the emergency response effort to come to an end, United States Coast Guard officials announced Monday afternoon.
The sheen spotted March 7 prompted quick response from the United Command, a group of several agencies that combine efforts to contain oil off the coast, formed following the 2021 oil spill in the same area that reached shore and impacted everything from beach access to businesses along the coastline.
Preliminary laboratory results of samples of the oil analyzed by the Office of Spill Prevention and Response – part of the Department of Fish and Wildlife – confirmed the release is lightly weathered crude oil and not a refined product, such as gasoline or diesel, but the Petroleum Chemistry Lab was unable to definitively identify the oil source, the Coast Guard said in its announcement Monday.
The samples are consistent with local crude oil, officials said, with characteristics of the Monterey Formation, and not imported oil that may have been brought by ship to California. The lab results were also inconsistent with archived samples from oil platforms in the area.
Earlier in the day, US Coast Guard public affairs specialist Richard Uranga said samples were thought to be from natural sources of seepage. But later in the day, a Coast Guard update said lab results were also inconsistent with archived samples from the area of both refinery oil and naturally released oil.
The samples do not match any in the CDFW database that covers the past 25 years, said Coast Guard Petty Officer Richard Brahm.
“That’s really where we’re at. They’ll keep taking samples of all this stuff until maybe they get a hit, or maybe they don’t,” he said. “I wish we had an answer. It’s definitely from the area, but we can’t pinpoint where it came from.”
The Coast Guard received a report about 7 p.m. on Thursday, March 7, from the National Response Center about the sheen on the ocean’s surface off Huntington Beach’s coast. It was first spotted about 2.8 miles off Huntington Beach near two oil platforms, Emmy and Eva. It was visually confirmed at first light the next day and containment efforts began.
Operations are now complete, currently in the “decontamination phase” cleaning booms and boats, Uranga said.
The preliminary laboratory results indicate that the oil samples analyzed from this incident are more characteristic of freshly produced oil than heavily weathered oil, which is associated with typical natural seeps, according to the USCG statement.
According to the National Oceanic Atmospheric Administration, crude oil entering the ocean is known as “seeps” and add about five million gallons of oil into the ocean each year.
While seeps are from a natural source, they can appear similar appearance and behavior and have similar effects as oil released during drilling and other human activities.
Both natural and processed oil can have environmental impacts and be toxic to fish, sea stars and shrimp, with the toxic effects largely limited to the immediate area of the release. More than 1,000 birds each year are oiled in Southern and Central California, primarily due to natural seeps, according to NOAA.
In this latest incident, two oiled birds died and several more were brought in for observation and cleaning, officials said. Tar balls washed ashore in the areas of Huntington Beach’s Dog Beach.
Waste disposal company US Ecology was contracted for the cleanup by the Coast Guard, with an estimated 1,050 pounds of oil waste, such as tar balls, collected and disposed of and 85 gallons of oil collected from the water.
While it is believed this was a one-time event, samples will be taken for additional analysis if another release is observed, Coast Guard officials said in their Monday update, noting Huntington Beach lifeguards will continue to monitor the beach for tar balls.
Brahm said if there’s a silver lining, it’s how quickly all the agencies got together to respond. By Friday, 85% of the sheen on the water had been cleaned up. By Sunday, an estimated 80% of the shoreline was cleaned.
“Everybody worked together flawlessly, quickly containing what was found, getting it cleaned up as quick as possible and protection booms were set out along several sensitive areas along the coast to minimize negative impacts,” he said. “It happened because we come together and do exercises constantly, and when something happens, we’re able to work together to minimize impacts and get stuff cleaned up really fast.”