Contra Costa County hazardous materials crews have determined the substance in a trailer that was left abandoned on a main road in Martinez was vegetable oil in a mislabeled container.
Crews responded shortly before 9:30 a.m. Tuesday to investigate an abandoned trailer on wheels along the 3300 block of Pacheco Boulevard and learned it had been tagged by the county Sheriff's Office as abandoned on March 4, Contra Costa County Fire Protection District Capt. Chris Toler said.
The trailer has "the type of container that normally carries everything from hazardous materials to milk" and had enough of the substance to prevent a responding tow truck crew from being able to tow it away, Toler said.
There were no identifiable markings or license plate to help investigators determine what was inside the container, so hazmat technicians were called out to figure out the nature of the substance, according to Toler.
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Pacheco Boulevard was blocked in both directions between Howe Road and Morello Avenue during the investigation.
Crews cleared the area before 2 p.m.
