HOUSTON, May 30 (Reuters) - Union leaders and Tesoro Corp managers met with a federal mediator on Wednesday in a last-ditch effort to avert a strike.
United Steelworkers union (USW) Local 5 members at Tesoro's 166,000 barrel per day (bpd) Martinez, California, refinery rejected the company's last contract offer on May 21 and had previously authorized their leaders to call a strike if talks failed.
"These talks are ongoing and we are optimistic a resolution will be reached," said Tesoro spokeswoman Tina Barbee.
Workers at six of Tesoro's seven refineries are represented by the USW and five refineries have voted to accept the contract Tesoro offered after contentious talks over worker safety and benefits that led workers at four plants to authorize strikes.
Only workers at the Martinez refinery, in the San Francisco Bay area, have refused to accept Tesoro's contract proposals.
"We're hopeful today's talks will bring a resolution to the outstanding issues Local 5 has with Tesoro's offer," said USW spokeswoman Lynne Hancock.
Tesoro has said that in case of a work stoppage it will halt production at the Martinez refinery until temporary replacement workers are trained to take over operating processing units and then it will resume production.