RELATED: Long Beach Shoreline Reopens After Tar Ball Cleanup
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RELATED: Thousands of Gallons Of Oil Sopped Up From California Coast
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The finding is the first confirmation that tar found on Southern California beaches came from the Plains All American Pipeline that dumped up to 101,000 gallons of crude oil on the coast May 19.
Federal regulators are investigating the spill's cause.
Tar balls washed up on Ventura County and Los Angeles County beaches about a week after the spill.
Plains has spent more than $65 million on cleanup costs in Santa Barbara County. The company says it has not been assessed for any Los Angeles cleanup.
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