Union members are calling on Chevron to keep wages up with rising inflation and health insurance costs.
"A cost of living increase for the Bay Area it's not for us to get rich," said B.K. White, First V.P. USW Local 5. "Our medical, Kaiser went up 23 percent this year and the company did not contribute another penny to it."
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The striking members make up roughly a third of workers at the refinery; they are lab technicians, warehouse workers, and maintain machinery.
In a statement, Chevron said it is "fully prepared to continue normal operations to safely and reliably provide the products that consumers need...We believe our contract offer is fair, competitive, and responsive to USW concerns."
As far as whether this strike will impact gas prices, UC Berkeley Professor Severin Borenstein said it depends.
"That will depend on two major factors, one is how much Chevron has to ratchet down production from this refinery," said Borenstein. "it's claiming it will be able to continue to produce, but I think we just don't know how much output will go down."
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The second major factor said Borenstein is that if the output does go down, how quickly can California bring in gasoline.
The worst-case scenario is we lose a lot of output from this refinery which is producing more than 10 percent of California refined products and it takes a few weeks or longer to replace it. If that happens - well - he says you'll likely be paying more at the pump.