Feds: 'Human error' blamed for San Fran oil spill

OAKLAND, Calif. -- Federal officials want a bird's-eye view of San Francisco Bay to observe environmental damage caused by the area's worst oil spill in nearly two decades.

U.S. Sen. Dianne Feinstein, D-Calif., and Coast Guard Commandant Adm. Thad Allen planned to take an aerial tour of the damage Sunday.

A preliminary Coast Guard investigation found that "human error," not mechanical failure, caused the cargo ship Cosco Busan to sideswipe a support on the San Francisco-Oakland Bay Bridge, leaving a gash nearly 100 feet long on the side of the 926-foot vessel.

"There were skilled enough individuals on board this ship. They didn't carry out their missions correctly," said Rear Adm. Craig Bone, the Coast Guard's top official in California.

The crash Wednesday ruptured two of the vessel's fuel tanks, which leaked about 58,000 gallons of heavy bunker fuel into the bay, killing sea birds and spurring the closure of nearly two dozen beaches and piers.

Feinstein and Sen. Barbara Boxer, D-Calif., have both called for swift and thorough investigations of the spill and Gov. Arnold Schwarzenegger has declared a state of emergency.

Meanwhile, efforts to clean up the mess have intensified. The Coast Guard increased the number of ships to 20 from 11 to work on skimming the oil from the bay, said Petty Ofc. Sherri Eng.

Nearly 20,000 gallons of oily liquid had been sucked up by Saturday morning, and about 770 workers have taken part in cleanup efforts on the water and along beaches to mop up the damage -- a job that is expected to last weeks or possibly months.

Rescue teams raced to save hundreds of seabirds tarred with black shipping fuel. At least 60 birds were found dead while 200 live birds were recovered and sent to a rehabilitation center in Solano County.

As cleanup continued, so did efforts to determine the oil spill's cause. While Coast Guard officials have not blamed a specific individual or detailed mistakes that were made, they have focused on possible communication problems.

Investigators were focusing on possible communication problems between the ship's crew, the pilot guiding the vessel and the Vessel Traffic Service, the Coast Guard station that monitors the bay's shipping traffic.

Coast Guard Cmdr. Andrew Wood said "the mere fact that they collided with a fixed object" offered clear evidence that a communication problem had occurred.

But a language barrier between the vessel's pilot, Capt. John Cota, and the ship's all-Chinese crew was not likely a factor in the crash, since the ship's captain and officers are required to speak English, officials said.

Bone acknowledged that there were communications between the ship and the Coast Guard's traffic facility before the collision. He said the communications involved the ship's course and speed but declined to comment further on the nature of the exchange.

Cota's lawyer, John Meadows, told The San Francisco Chronicle that the nearby Coast Guard facility radioed Cota and questioned his bearings. The pilot immediately responded by saying the ship's instruments showed he was on the correct heading, Meadows told the newspaper.

The spill has also spurred about 65 Bay Area crab fisherman to vote to ask Gov. Arnold Schwarzenegger to officially close the commercial and sport crabbing seasons.