Unions say they made more than $100 million in concessions during 2009 contract talks, and amid an official blackout on details of negotiations are reportedly seeking a 20 percent pay increase over the next three years. They're also seeking to limit the amount pay for medical benefits (they currently pay a flat $92 a month for family coverage) and for pensions (currently, workers do not contribute to their pension plan). BART has offered an 8 percent pay raise over four years, an increase that would be offset by contributions to benefits and pensions.

In response to the unions' 72-hour strike notice, BART spokesman Rick Rice said another strike would only delay the decision-making process.

"We are very disappointed and hope they reconsider their options. A strike only stalls and delays the decisions that need to be made while using our riders as pawns."

Rice also insisted BART is committed to continue negotiations. “BART is willing to stay at the table for as long as it takes to reach an agreement. Even if there isn’t a deal in place by Sunday night, talks can be extended," he said. BART management earlier disclosed it has not moved from on its main offers on pay, pensions, and benefits for the past month.

SEIU Local 1021 President Roxanne Sanchez criticized management for a lack of progress in the negotiations.

“It is unfortunate that we find ourselves in the same situation that we were in 30 days ago, with no real progress made by management to address worker concerns about safety and wage cuts," she said.

“BART management...continue to attack workers in the press when they should have been finding ways to make BART safe and focusing on reaching a fair agreement."

Earlier, one union leader said progress had been made on peripheral issues, but other issues, including salaries and benefits, have yet to be resolved.

Regional transportation officials projected in the event of another BART strike, ‎traffic would jump 10 percent over the last shutdown, which started during the Fourth of July weekend when many people were away on vacation. Despite this projection, officials do not plan to offer more alternative buses and trains than they did last time. BART says it will have about 95 charter buses to transport Bay Area commuters should workers strike.

The KPIX poll released today found that by a 2:1 ratio, respondents feel BART has made the stronger case for its position. The SurveyUSA poll of 800 Bay Area adults found that 44 percent of those who said they have been following negotiations felt management had made the better case as opposed to 19 percent who felt the unions' case is stronger. The Bay Area Council, a business group that estimated that last month's BART shutdown cost $73 million a day, released a poll of 475 residents of San Francisco, Alameda, Contra Costa and San Mateo counties that shows 70 percent of all respondents oppose a strike.

SFO outlines transit options in event of a strike.

Unions give 72-hour strike notice. Details and commute options: http://t.co/Z8IgGR3vVH

— SFBART (@SFBART) August 2, 2013

#casualcarpool, Carpooling is your best option during a #BARTstrike, visit http://t.co/e7AIyu05WF for tips: http://t.co/a7HjdC7wsT

— 511 Bay Area (@511SFBay) August 2, 2013

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