A team of federal mediators bowed out of the BART contract negotiations today as union representatives announced that the talks have failed and workers will strike at midnight.

“I’m sorry, I’m regretful,” Service Employees International Union Local 1021 President Roxanne Sanchez said at a news conference outside Caltrans offices on Grand Avenue in Oakland where negotiations have been taking place.

“The employer has been unwilling to reach an agreement or to settle these disputes without a strike,” Sanchez said.

Federal mediator George Cohen said the two sides have reached agreements on “a number of very significant items that have previously separated them” but that sticking points remain and no one is budging.

“The parties were unable to bridge the gap,” Cohen said. “Our efforts to do that at this point in time were not successful.”

The three-person federal mediation team decided there was “nothing further we were able to do,” he said.

The news conference came after a marathon 30-hour negotiating session.

“We came here at 10 o’clock yesterday morning. We have not left,” Amalgamated Transit Union Local 1555 president Antonette Bryant said.

If no surprise agreement is reached before midnight, trains will not be running for the morning commute.

Trains already in operation at midnight will continue running until the normally scheduled end of service.

Bryant said she is “deeply disappointed” at the outcome of the marathon session but blamed management.

“We were this close and yet at the last minute they threw in a management rights clause to take away our rights as workers,” she said. “Everything else was done. It should have been done.”

“This is not an economic strike,” Bryant said. “It is an unfair labor practices strike.”

BART General Manager Grace Crunican then spoke, saying management had offered a 12 percent raise over four years, with workers paying a 4 percent pension contribution and a 9.5 percent increase in their health care contributions.

Crunican said the sticking points related to management’s proposed work rules, which she said are essential to maintaining BART’s effectiveness.

“As we’ve gone back and forth, the district made it clear that we had certain rights that we had to maintain in this package,” she said.

Crunican said the rights laid out in the proposal give management the flexibility it needs to maintain an efficient system and cut out wasteful practices.

She gave an example of pay stubs, saying management needs the ability to have pay stubs delivered electronically rather than be required to have a worker deliver paper stubs to employees.

Crunican said BART management’s offer will expire on Oct. 27 if the unions don’t accept it.

Negotiators for management and the two unions also participated in lengthy bargaining sessions earlier this week.

Talks that began on Monday didn’t end until 5:30 a.m. the following day, and talks that began on Tuesday afternoon lasted until about 1 a.m. Wednesday.

BART workers previously went on strike for four and a half days at the beginning of July, after their previous contract expired, but they have been at work since then as negotiations have continued.

Lt. Gov. Gavin Newsom has been at the table for some of the negotiations this week, and earlier this afternoon predicted that today could be a turning point toward a deal or worker walkout.

“You get to a point where you feel your back is up against the wall,” Newsom told reporters at an unrelated event in San Francisco.

He said the unions could strike because “people will do things sometimes that are not in their best interest because they think there are no other alternatives.”

Newsom said BART management representatives might feel like they have the support of the public, but if there’s a strike, “no one’s a winner.”

“We can’t allow that to happen,” he said.