MARTINEZ (KCBS) – Contra Costa County stands to lose millions of dollars in future property tax revenue from oil refineries, and may even pay a hefty refund to Chevron, because of an appeal’s court’s decision governing how refineries compute the value of their equipment.

“There would be a substantial tax refund, in the millions of dollars. It could very well be over $10 million, but it hasn’t been calculated,” said Contra Costa County Supervisor John Gioia.

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KCBS’ Chris Filippi Reports:

The appeals court ruling in January tosses out a state rule that oil companies argued unfairly singled them out with tax burdens that did not apply to other industries.

Rule 474 limited how much a refinery could write down the value of old equipment by assessing the value of the equipment, the buildings and land as a single unit rather than individually.

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“When you buy and sell a refinery, you’re selling the land and the equipment together,” Gioia said.

“If the California Supreme Court does not uphold Rule 474, this could cost us millions of dollars in tax revenue in the future.”

The county Board of Supervisors voted last week to join with the California Board of Equalization if it takes the tax fight to the state Supreme Court.

The state Board of Equalization has until Feb. 28 to petition the state supreme court for a hearing.

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