A few of over one hundred tarballs collected on some southern California beaches were tested found to have come from the Santa Barbara oil spill that occurred on May 19 just north of Refugio Beach. Some samples were also connected to naturally occurring ocean floor seepage.

Tarballs have been washing ashore at beaches up and down the southern California coast for weeks, leaving beachgoers and scientists questioning the source. After the May 19 Refugio oil spill, the question of a link between occurrences and the spill arose.

California Department of Fish and Wildlife officials gathered over 100 samples from Santa Barbara County, Ventura County and El Segundo, Manhattan, Hermosa and Redondo beaches according to public radio station KPCC. One of those balls collected from Manhattan Beach was found to have a connection to the Santa Barbara spill. Manhattan Beach is roughly 100 miles south of Santa Barbara.

An estimated 21,000 of the 105,000 gallons of crude released in the Santa Barbara spill are believed to have made it out to sea, according to an earlier Associated Press report.

Plains All American, the company responsible for the May 19 oil spill, said in a Monday statement that the United States Coast Guard collected nine samples from Manhattan Beach, six of which have come back from testing so far. In results shared with Plains, two of the balls were found to have a connection to the spill and four were “consistent with samples from natural seeps in the Santa Barbara region.”

Environmental activists are using the samples to push for increased oil regulations and strong legal action against Plains All American, as detailed in a Heal the Bay statement.

Naturally occurring tarballs have been showing up on beaches for decades, sticking to barefooted visitors. The natural phenomenon appears when the earth moves on the ocean floor, releasing oil deposits. The material then floats to shore. On the shore the oil coagulates, forming what looks like gooey little tarballs.

The definitive source determination of tarballs found at other beaches–including San Diego’s Pacific Beach, Del Mar, Carlsbad and Long Beach–is still under investigation. Some of these incidents preceded the Santa Barbara spill.

Photo: File (France)

Follow Michelle Moons on Twitter @MichelleDiana