RODEO (CBS SF) — An oil spill was reported Monday morning in the San Pablo Bay near the Phillips 66 refinery in unincorporated Contra Costa County, the U.S. Coast Guard and the state Office of Emergency Services said.

The spill was reported at about 8:15 a.m. just off the coast of 1380 San Pablo Ave. in the community of Rodeo. Coast Guard officials responded to the area.

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Though the reporting party said a 20-foot by 20-foot sheen was visible on the bay, Coast responders did not see a sheen, Coast Guard Lt. Nicole Emmons said.

But Emmons said a gas and oil mixture was determined to be coming from a pipe.

According to a report by the OES, the reporting party said that the leak had been stopped by 9:30 a.m.

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The leak was caused by a broken pipe, the OES said.

Officials from Phillips 66 did not immediately respond to a request for comment.

About 9,000 hazardous material spills were reported statewide last year, according to the OES.

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