Market Union Sets ‘Absolute’ Deadline for Strike Tonight : Labor dispute: Optimism fades after marathon talks. Negotiators say they’ll make one more try.

After little progress was made in a marathon 18-hour session, exhausted negotiators in the Southern California supermarket contract dispute said Wednesday they would make one more stab today at averting a strike.

Leaders of the United Food and Commercial Workers Union, which represents 80,000 clerks and meat cutters at 800 markets from San Diego to Bakersfield, set an “absolute” deadline of 7 o’clock tonight to either reach agreement on a new three-year contract or strike.

A strike would affect the region’s six largest chains: Lucky, Albertson’s, Alpha Beta, Ralphs, Stater Bros. and Vons. The markets say they would staff their stores with a combination of strikebreakers, non-striking employees and managers.

When negotiations resumed Tuesday afternoon, both sides were expressing optimism that they could craft a settlement balancing the markets’ demands for cost cutting with the union’s demand that job security concerns such as guaranteed hours be met.

Within hours the optimism faded. Talks went through the night, ending about 7 a.m Wednesday.

“After several days of marathon bargaining, we have reached a crisis situation,” said Tom Vandevelt, president of UFCW’s San Diego-based Local 135, one of 10 locals involved in the negotiations.

“For a while, I had been optimistic that we might conclude these negotiations without a strike. This morning at 6 a.m., all our efforts of putting together an agreement seemed to unwind,” Vandevelt said.

Later Wednesday the two sides declared a news blackout.

Negotiators for both sides were believed to be conferring with their leaders to determine how much flexibility remains. Chief executive officers of the supermarket chains have not been present at the talks. National executives of the union, dispatched from Washington, have been directly involved and are regarded as having influence over presidents of the locals in critical situations.

The old contract expired July 30. Assessments of negotiations have ranged from disappointing to promising and back again. Key issues include union demands for more guaranteed hours of work, supermarket demands for a cheaper and less flexible medical benefit package and the union’s demand for restrictions on the use of non-union vendors. Some of these issues were taken “off the table” in 1987 to avoid a strike then.

Dan Mitchell, a collective bargaining expert in UCLA’s School of Management, said the fact that there have been several extensions of union strike deadlines indicates that the two sides believe they are resonably close to a settlement.

“A normal reading of that is that they thought when they extended it they’d make progress,” he said.