The subcommittee, which included House Speaker Nancy Pelosi, D-San Francisco, was particularly upset by National Transportation Safety Board officials, who said their investigation into the disaster could take a year to complete.

"I wasn't satisfied with the answers or the path that we were on," Pelosi said after the three-hour hearing in the Presidio held by the House Subcommittee on Coast Guard and Maritime Transportation. "I don't think they have the credibility to self-examine or self-investigate."

The hearing was an effort to get to the bottom of a myriad of apparent problems that plagued the cleanup operation after the cargo ship Cosco Busan sideswiped the Bay Bridge on Nov. 7, and spilled 58,000 gallons of bunker fuel into the bay.

The spill fouled beaches along a 40-mile stretch of coastline after being swept away by the strong bay currents.

Lawmakers want to know why the ship hit the bridge, why there was an hour delay in reporting the spill and nearly a 12-hour delay in announcing its severity. There are also questions about whether the Coast Guard should have acted more quickly and aggressively.

The district commander for the U.S. Coast Guard apologized for not communicating the severity of the spill in a timely fashion, but said that the cleanup response to the spill was excellent.

Meanwhile, more birds have been rehabilitated and released today.

About 35 birds - including common murres, surf scoters, western grebes, and a ruddy turnstone - were released at Heart's Desire Beach on Tomales Bay.

More than 1,000 birds have been covered in oil and are undergoing rehabilitation at the Oiled Wildlife Care Network in Cordelia. Saving a bird takes about 10 days, depending on how injured it was when it was found, wildlife workers said.

Some beaches have been opened since the oil spill happened about two weeks ago. Residents can call (415) 398-9617 to report oil on beaches.