United Steelworkers at Tesoro Corp.'s Wilmington refinery in Los Angeles have voted to strike if their bargaining committee gives the OK, the union said Thursday in a prepared statement.
The vote marks the fourth strike authorization at plants owned by the San Antonio-based refiner.
USW members earlier gave their respective bargaining committees permission to strike at Tesoro's plants in Martinez, Calif., Anacortes, Wash., and Mandan, N.D.
The USW's contracts at the four plants cover 979 workers.
"We are doing everything we can to negotiate in good faith and obtain a fair contract, but if Tesoro fails to do the same, they'll give us no option other than to strike," said Local 675 Tesoro Unit Chair Ryan Heustis.
Tesoro spokeswoman Tina Barbee didn't respond to a request for comment, but in a statement on its website, Tesoro said it continues to bargain in good faith.
The company noted that the strike authorization vote "allows (USW members) to go on strike without further voting by represented employees - but we have not been given notice of intent to strike, and the parties continue to meet."
The company said it has made contingency plans in the event of a strike.
The vote at the Wilmington plant took place Tuesday and Wednesday, the USW said, on a contract to replace one expiring April 30.
The USW contends that Tesoro has reduced certain benefits under existing contracts, and wants contracts under negotiation to allow such cuts.
Following cuts to benefits, the union filed unfair labor charges with the National Labor Relations Board.
An administration law judge heard the union's charge in March and a decision is pending, the USW said.
San Antonio-based Tesoro has seven refineries.
USW members have ratified a contract at the company's Salt Lake City plant and at its Hawaii refinery.
Tesoro has said it hopes to close on a sale of the Hawaii plant in the current quarter.
Tesoro's refinery in Alaska is non-union.
Copyright 2012 San Antonio Express-News. All Rights Reserved.
(Originally published April 20, 2012, in the San Antonio Express-News.)