OAKLAND -- Caltrans officials told transportation commissioners it will not commit to opening the new eastern span of the Bay Bridge on Labor Day until there are answers to why huge steel bolts snapped last month, and a solution to ensure the seismic safety of the bridge.

However, Caltrans Deputy Executive Director Andrew B. Fremier told the media that the agency would "actively consider" opening the bridge without a fix if it determined that it would be safer to use than the old span.

The revelations came during a Caltrans presentation on the bolt problem during a Metropolitan Transportation Commission meeting Wednesday morning.

California Transportation Commission Chief Engineer Stephen Maller made the comments, raising concerns that the span will not be ready in time to open on Labor Day as planned.

Calling it the "first real construction problem they've had," Caltrans engineers told Berkeley Mayor and MTC commissioner Tom Bates that it would be "guess work" to say for sure that the Labor Day date will stand.

Oakland Mayor Jean Quan said her city needs timely notification of any possible delay in the bridge's opening to help avoid impacts to local businesses, particularly hotels.

The bolts that snapped last month connect steel earthquake safety devices called shear keys to the deck of the span and a large concrete cap.

-- Staff writer Lisa Vorderbrueggen and The Associated Press contributed to this report.