Oil Slick Near Holly Likely from Natural Seepage

Drone footage shot over Platform Holly last week surfaced on social media, raising fears of an oil leak at the facility. Shot by Steven Gute, a documentary maker apparently based in Hollywood, the footage shows a slick of rainbow coloration around and down current of Holly, as well as a smaller area up current a couple hundred feet from the platform. That was a giveaway, said David Valentine, a geochemist at UC Santa Barbara, whose department has tracked oil in the Santa Barbara Channel for decades.

The Coast Guard went out to take a look; the State Lands Commission is investigating — the agency is closing down Platform Holly and held a town hall meeting about it the day before Gute first spotted the rainbow sheen on December 10; and the Office of Spill Prevention and Response obtained a sample of what appears to be an oil slick. They were all fairly certain it was from a natural seep, which is Valentine’s conclusion, too.

To the geochemist’s experienced eye, the slick was imaged as it floated eastward from an area just west of the platform, a zone included in graduate student Alex Padilla’s work to quantify the seeps of gas and oil in recent years, a paper she is currently working on, said Valentine. As well, the rainbow sheen and steely gray color indicated a fairly thin and recent seep rather than a thick oil flow, he noted. An older and thicker flow would be emulsified by the waves and tend to turn a spongy orange in color. Another reason he didn’t think it was an oil leak was because the platform’s wells had been nonoperational for more than six years. Holly shut down in May 2015, when the Plains All-American pipeline that moves oil out of the county rusted through, causing the Refugio Oil Spill and stopping oil production in the region.

Surfers had reportedly smelled strong whiffs of petroleum in the area, according to social media accounts. Gute, who contacted the Independent on Tuesday, said he often came to Santa Barbara to surf. He had posted his image out of concern it could presage a serious spill, he said, and had a documentary project called Confluence about environmental topics.

Valentine explained that seeps in the Santa Barbara Channel are mostly composed of gas bubbling upward, and they emit a strong smell of naphtha, or petroleum, more so than sulfur. “Oil is almost always present in the seeps,” he explained, “but not very much. Think of it like pasta with prawns. The oil is like the prawns, but there’s a lot more pasta.” From a small submersible, he’s seen the bubbles percolating upward out of dots in the sand; occasionally, a soft blob of oil floats up. As it surfaces, he described, the volatile chemicals in its makeup evaporate over time, and the blob gets gooed together with other globs and flotsam on the surface, as some eventually wash ashore to coat the underside of your feet.

Valentine’s is an early, albeit highly experienced, evaluation of the oil slick, but one shared by the agencies involved and also members of the environmental community in Santa Barbara. The oil samples are being evaluated at the state Petroleum Control Laboratory, and Valentine explained that natural seeps and oil from wells have distinct chemical “fingerprints” that distinguish one from another. Those results are expected within the week, said Steve Gonzales, with Fish & Wildlife. As well, no unusual conditions or release of oil was found at the platform or its well plugging over the weekend.

Update: This story was updated on December 14, 2021, to include Steve Gute’s comments. The date the Instagram photo was taken is December 12, 2021.

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