No Oil Found Aboard Sunken WWII Tanker

Technicans navigate the ROV around the sunken World War II tanker S.S. Montebello, Oct. 12, 2011. Photo by NOAA Robert Schwemmer

After 11 days of survey and sampling using both the latest in technology and physical sampling, no oil remains were found on the sunken World War II tanker, SS Montebello.

An on-scene assessment conducted by the Coast Guard and California Department of Fish and Game’s Office of Spill Prevention and Response of the tanker, which happens to be located just miles from gCaptain’s hometown of Morro Bay, California, has determined that there is no substantial oil threat from the Montebello to the surrounding waters and shorelines.

ss montebello explosionThe S.S. Montebello sank after a Japanese submarine torpedoed the large oil tanker on December 23, 1941. The vessel broke apart landing upright with her bow separated from the majority of the wreckage. At the time of sinking no release of the 3.2 million gallon cargo was observed.

Over the past few days Global Diving & Salvage, working under the direction of the unified command , has assessed cargo and fuel tanks as well as collected ocean floor sediment samples. “Our number one objective for this mission was to determine what threat, if any, the Montebello poses to the waters and shorelines of California,” said Coast Guard Capt. Roger Laferriere. “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.”

With the assistance of its Cougar XT ROV Global combined visual and sonar imaginary into 3D models of the vessel. These models where then combined with data from thickness gauging, backscatter tooling, samples of the tank contents  and nearby sediment to determine the results.

“Knowing that this wreck does not pose a significant pollution threat is great news”, says Devon Grennan, President of Global Diving & Salvage, Inc. “The combination of the latest technology, sound planning and project management, excellent collaboration between Federal, State and private enterprise shows the possibilities in investigating these deep water wrecks and the ability to determine the pollution potential.

“This is a new era of prevention,” said DFG OSPR Capt. Chris Graff. “This has been a cooperative partnership using cutting-edge technology and surgical precision. The procedures and techniques used could help conduct threat assessments on other sunken vessels.”