8 Months After Chevron Oil Refinery Spill, Few Answers Surface About Cause

In the eight months since hundreds of gallons of fuel from Chevron's Richmond oil refinery spilled into the bay, local air regulators and the state's workplace safety agency have issued a handful of violation notices against the oil giant.

But neither Chevron nor the agencies investigating the Feb. 9 incident has provided details about exactly what caused a pipeline on the refinery's wharf to spill as many as 750 gallons of low-sulfur diesel fuel, creating a sheen that spread for several miles across the bay.