GOLETA, Calif. (CBS/AP) — Cleanup teams have determined that 44 percent of 96.5 miles of California coastline is clear of oil from the Refugio Oil Spill, a state official said Sunday.

The 44 percent includes mostly sandy beaches, which only have trace amounts, or less than 1 percent of oil, said California Department of Fish and Wildlife spokeswoman Alexia Retallack. She said tar and oil is naturally found through seeps at Southern California beaches and should be avoided.

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Cleanup efforts span from northern Santa Barbara County into Ventura County. What’s left is more intensive and includes cobbled beaches. Retallack said there is no timeline for completion of the cleanup efforts and that some already cleared shoreline areas are still being monitored to ensure they aren’t re-oiled.

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Oil blackened beaches in the area and created a 10-square-mile slick in the ocean after the onshore pipeline leaked up to 101,000 gallons on May 19.

More than 1,000 workers from local, state and federal agencies have been working to clean up the beaches, examining the areas at high and low tide, looking below the sand down to two feet and all rock and other beach structures for oils.

The spill has killed one sea lion, nine pelicans and untold numbers of fish. El Refugio and El Capitan beaches remain closed.

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