Officials say a World War II oil tanker carrying three million gallons of crude that was sunk off the Pacific Coast by a Japanese torpedo doesn't pose an oil spill risk.
The announcement came Thursday following an investigation by the Department of Fish and Game to see if any oil remained in the hold of the 440-foot S.S. Montebello.
The investigation was inspired by last year's Gulf of Mexico oil spill, and a fear of what any remaining oil could do to the celebrated stretch of California's Central Coast below Hearst Castle.
"After careful evaluation of the data, we have concluded with a high level of confidence that there is no oil threat from the S.S. Montebello," Coast Guard Capt. Roger Laferriere said.
The ship was hauling the oil from California to Canada the day of the attack in 1941.
The Montebello has been sitting upright ever since, 900 feet below the surface about six miles off Cambria.
Officials have assessed cargo and fuel tanks and have collected ocean floor sediment samples using an underwater remotely operated vehicle.
The samples are being sent out for further analysis.
The $5 million operation was funded by a tax paid for by the oil industry.
NOAA Scientific Support Coordinator Jordan Stout said it seems reasonable that the oil may have remained off shore and headed south before washing ashore on a wide swath of land, making it unnoticeable.
But Stout said there are "a number of unknowns associated with this release. Therefore, we will probably never know exactly what happened to the oil."
Fish and Game took park in the operation with the U.S. Coast Guard and the National Oceanic and Atmospheric Administration. A final report is expected next spring.