Union leaders called strikes on Sunday at nine U.S. refineries in a bid to pressure oil companies to agree to a new national contract covering workers at 63 plants. The walkouts, the first held in support of a nationwide pact since 1980, target plants that together account for more than 10 percent of U.S. refining capacity. The discord comes as plunging crude prices force oil companies to slash spending. Royal Dutch Shell, the lead industry negotiator, indicated talks had broken down. ... Shell activated a strike contingency plan at its sprawling joint venture refinery in Deer Park, Texas, to keep...
