More than 500 workers at a Chevron refinery in the San Francisco Bay Area officially went on strike at Monday morning.
Members of United Steelworkers Local 5 voted down the company's most recent contract offer and gave notice of intent to go on strike, the union said in a statement Sunday.
The statement says Chevron refused to return to the bargaining table.
Chevron said in a statement Sunday night that it has negotiated with the union for months and believes the contract offered was fair and addressed union concerns.
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If the strike shuts down the Richmond, California, refinery, it could crimp gasoline supplies in the state, which has the highest regular gas price in the nation at $5.847 per gallon, according to AAA.
The union said in its statement that it reached a pattern agreement with the oil industry Feb. 25 on wages and working conditions. But about 200 bargaining units also have to agree on local issues before contracts can be approved.
But Chevron argued that “the union's demands exceeded what the company believes to be reasonable and moved beyond what was agreed to as part of the national pattern bargaining agreement.”
The old contract with Chevron in Richmond expired Feb. 1, and workers have been reporting to their jobs on a rolling 24-hour extension, the union said.
The company says that operations at the refinery will continue and it does not anticipate any supply chain issues.
The San Ramon, California-based Chevron says on its website that the refinery produces gasoline, diesel and jet fuel, as well as lubricating oils.