The leaders of the California Senate and Assembly committees on transportation said they would hold separate hearings later this month to examine the issues raised in The Bee investigation Sunday about Caltrans testing problems involving the new Bay Bridge and other freeway structures.

"It's a concern for anybody who sits behind the wheel. I was shocked when I learned about this mismanagement and I have a lot of questions about the issue and I expect to follow up and get a lot of answers," said Bonnie Lowenthal, D-Long Beach, chair of the Assembly Committee on Transportation.

The Bee investigation documented three test fabrications and numerous other errors by a Caltrans technician, casting doubt on his data on dozens of freeway structures across the state. Those include the main tower of the new eastern span of the Bay Bridge, scheduled for completion in 2013.

Caltrans officials have insisted that the Bay Bridge and all other structures are safe, but so far have declined to release documents that validate their assertions.

Senator Mark DeSaulnier, D-Concord, chair of the Senate Transportation and Housing Committee, said he would hold a hearing about the safety of the new eastern span of the Bay Bridge, and how the Caltrans testing process broke down. He said the focus would be ensuring that no similar problems emerge in the future.

"We'll do our due diligence, and we have time before the bridge opens to make sure it's safe," DeSaulnier said.

Rep. Nancy Pelosi, D-San Francisco, minority leader of the U.S. House of Representatives, whose district includes much of the Bay Bridge, also expressed concern.

"Leader Pelosi believes that safety of our infrastructure must be the number one priority of Caltrans," said Carlos Sanchez, Pelosi's deputy press secretary. "Our office has already reached out to Caltrans and (the Federal Highway Administration) to seek a full explanation of what occurred and what will be done to assure the safety of the traveling public now and in the future."

The Bee examined about 50,000 internal Caltrans documents - including data, test reports and personnel files. They showed that Caltrans officials knew about the testing problems for years, but failed to conduct a comprehensive investigation despite public safety concerns raised by insiders.

Lowenthal said that her committee would demand proof from the agency that it had not mishandled its testing responsibilities.

"We will have backup for any assertions made on structural integrity," she said.

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