Pictured is an announcement displayed on the door at the entrance of Vons. The supermarket chain is preparing for a possible strike. For now, the strike approved by 90 percent of grocery workers has been put on hold after federal mediators ordered “intensive negotiations” between parties. A Southern California grocery workers union representing 62,000 members whose contracts with the three major supermarket chains, Vons, Albertsons and Ralphs, expired six months ago, voted two weeks ago to authorize a strike if necessary. Soon after the vote, a federal mediator ordered the unions and the three major supermarket chains resume “intensive negotiations” by Monday, Aug. 29. Union representatives say the negotiations have been drawn out over the past eight months, and they have yet to discuss wage and labor condition rules with the chains. According to officials for Ralphs, Albertsons and Vons, employees will be required to pay $9 a week for single coverage, while the cost of family coverage under the proposal would be $23. The healthcare proposal would maintain the current prescription drug co-payments and the annual deductible and outofpocket maximums in the PPO plan, according to the grocery chains. Under an HMO option, there would be no change to medication co-payments.