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(Recasts with USW making counterproposal)
HOUSTON, Feb 12 (Reuters) - The largest U.S. refinery strikesince 1980 entered its 12th day on Thursday with no talksscheduled until next week and industry representatives wereweighing a union counterproposal, said a labor spokeswoman.
No details were provided about the counterpropasal by theUnited Steelworkers union (USW) or when it was passed to leadU.S. refiner negotiator Shell Oil Co, said USW spokeswoman LynneHancock.
"The USW is waiting to receive the information it requestedfrom Shell and for Shell to respond to the USW'scounterproposal," Hancock said.
Shell told the union on Wednesday it would need a week tocompile a response to answer an extensive information requestfrom the USW about the use of non-union contractors inrefineries. Talks are scheduled to resume on Wednesday, Feb. 18
The USW has said that non-union workers hired by companiescontracted to do regular refinery maintenance are less qualifiedthan union workers.
Also on Thursday, Tesoro Corp Chief FinancialOfficer Steven Sterin told analysts during an earningsconference call that production at the company's166,000-barrel-per-day (bpd) refinery in Martinez, California,will remain shut down until the strike ends.
Two of Tesoro's California refineries and another inWashington are among nine refineries where workers are onstrike, affecting 13 percent of U.S. capacity. A chemical plantand power co-generation plant have also seen walkouts.
Tesoro is operating the Martinez refinery near San Franciscoas a terminal.
Tesoro Chief Executive Greg Goff said during the call thatit was too early to discuss hiring permanent replacements forthe striking workers.
Shell Oil Co, the U.S. arm of Royal Dutch Shell Plc, said it remained in contact with the USW.
"The lines of communication between the USW and Shell remainopen," Shell spokesman Ray Fisher said.
Since the talks started on Jan. 21, sticking points haveincluded the use of non-union contractors and how to monitorworker fatigue. Wage increases and health benefits are also onthe bargaining table.
The USW is seeking a three-year, industry-wide pact thatwould cover 30,000 workers at 63 U.S. refineries that togetheraccount for two-thirds of domestic capacity.
Over the weekend, walkouts widened to include BP Plc's Whiting, Indiana, refinery and its joint-venture refinerywith Husky Energy in Toledo, Ohio.
Companies have called on trained temporary replacementworkers to keep their plants running at nearly normal levels.
Refineries where the strikes are taking place have reportedmalfunctions since walkouts began on Feb. 1.
A 70,000-bpd gasoline-producing fluid catalytic crackingunit was shut earlier this week at Shell's 327,000-bpd refineryin the Houston suburb of Deer Park, Texas. (Reporting by Erwin Seba and Kristen Hays; Editing by PaulSimao, Bernard Orr)
