SAN FRANCISCO (CBS SF) – BART management has requested assistance from a state mediator because of stalled contract negotiations with its labor unions, the transit agency announced Tuesday.

Contracts between BART and several unions that represent more than 2,400 employees expire on June 30, and both sides were pushing for a compromise over wages and health benefits.

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The unions involved in the negotiations include Service Employees International Union Local 1021, Amalgamated Transit Union Local 1555, and American Federation of State, County and Municipal Employees Local 3993.

The transit agency Tuesday issued a statement confirming that BART management is asking for the assistance of a state mediator to “bridge a large gap in negotiations.”

“We’re also hoping to get some concessions and pension and medical costs and they’re not showing any willingness to concede whatsoever on that,” BART spokeswoman Alicia Trost said. “They have kind of drawn that line in the sand and so were hoping a state mediator will come and help and sort of get these negotiations going again.”

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The unions represent maintenance workers, mechanics, operators, station agents, supervisors and mid-level managers.

Antonette Bryant, president of ATU Local 1555 representing station agents and train operators, told KCBS on Tuesday morning that it’s too early to ask for outside help.

“We received a package from them on Monday afternoon. We haven’t even had a chance to fully explore that package, nor have they fully explored our proposal. So at this point, it seems premature to call someone in,” she said.

Both sides are scheduled to meet on Thursday and contracts between BART and the unions— that represent more than 2,400 employees—expires on June 30.

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