SAN JOSE, Calif. -- Trying to learn once and for all whether a 440-foot-long oil tanker sunk by a Japanese submarine in 1941 off the Central California coast still poses a risk of a catastrophic oil spill, a team of scientists is preparing to probe the wrecked ship with high-tech gear.
Nearly 70 years after it became an early casualty of World War II, the SS Montebello is resting in 900 feet of water on the sea floor, 6.5 miles west of Cambria, in San Luis Obispo County.
Since the shipwreck's discovery in 1996, the Coast Guard, state wildlife agencies and environmental groups have worried that the steel tanker, which held up to 3 million gallons of crude oil, could rust through. A resulting oil spill could blacken the California coastline, particularly the Monterey Bay National Marine Sanctuary, which is only about a mile from the wreck site.
"This ship sunk upright and intact," said Andrew Hughan, a spokesman for the California Department of Fish & Game. "If there is oil in that ship, eventually the oil is coming out, one way or another -- whether we devise a way to take it out, or whether there's an earthquake, and the ship rolls over and dumps 3 million gallons out."
The Coast Guard awarded a contract to Global Diving & Salvage Inc., a Seattle firm, for the work. Starting Wednesday, the company will send an unmanned, remotely operated vehicle into the deep, cold and dark ocean waters.
The unmanned vessel will drill into the ship to test for oil, and its consistency. The holes will be capped with valves to prevent leakage.
Researchers also will use high-tech imaging equipment to evaluate the integrity of the ship's steel. And they will test sediments around the vessel to determine whether oil has leaked out in the past. Hughan noted that previous dives evaluated the ship in 1996 and 2003, but today's technology is more advanced.
"There's been no indication that the hull hasn't maintained its integrity. It's solid steel construction," he said. "We've never seen any kind of oil leakage from it. The oil could be intact or completely gone. Our assumption is that there are still 3 million gallons in that ship."
The crews will work for about 10 days, and are expected to deliver a report six months later. The Coast Guard funded the mission, which will cost about $3 million, from the Oil Spill Liability Trust Fund. The federal account is funded by a 5-cent-per barrel fee imposed on the oil industry by Congress and President George H.W. Bush after the Exxon Valdez oil spill in 1989.
"The California coast is a vital national resource that we must protect," said Coast Guard Capt. Roger Laferriere, the federal coordinator on the scene.
If oil is found, there are basically three options:
--It could be left untouched, risking a catastrophic spill one day, but also leaving the possibility that future technology could better handle the problem.
--The oil could be pumped out, although it might have to be steam-heated first because its consistency in the 44-degree waters at 900 feet is probably like tar.
--It could be mixed with a liquid polymer, like plastic, and hardened into a solid mass. That strategy has been used to keep oil and diesel fuel from spilling after fishing boats and yachts have sunk.
"We hope it never does leak," said William Douros, West Coast marine sanctuaries manager for NOAA, the National Oceanic and Atmospheric Administration. "This project will let us know what the hull is doing and the oil is doing so people won't have to speculate any more."
California already experienced a serious oil spill from a sunken ship. In 2002, Coast Guard salvage divers pumped 85,000 gallons of fuel from the SS Jacob Luckenbach, a freighter that sank in 1953 about 17 miles west of San Francisco. That four-month cleanup, which cost $20 million, ended regular leaks from the ship which had killed as many as 50,000 sea birds between Monterey and Point Reyes National Seashore over a 10-year period.
The attack on the Montebello is not widely known today. But the ship's sinking made big headlines in 1941.
On Dec. 23, 1941, just 16 days after the bombing of Pearl Harbor, the tanker left Port San Luis, in San Luis Obispo County, shortly after 1 a.m., bound north for refineries in Vancouver, British Columbia.
Documents show the ship was carrying 75,346 barrels of crude oil -- about 3.1 million gallons. By comparison, the Exxon Valdez spilled 11 million gallons into Alaska's Prince William Sound.
Only four hours after leaving port, a lookout spotted an Imperial Japanese Navy submarine surfacing about 100 yards in the distance. The Montebello made a futile attempt to outrun the sub. At 5:55 a.m., a torpedo ripped into the tanker's bow.
The submarine then began shelling the tanker with a deck gun while 38 crew members raced for the lifeboats. The ship sank quickly. All of its crew escaped to safety after two tugboats steamed through heavy seas to assist.
"The ship's hold will eventually fail. It is a ticking time bomb," said Kaitilin Gaffney, Pacific program director for the Ocean Conservancy, an environmental group. "We just don't know how fast it's ticking. It could be months, it could be another 70 years. Hopefully the expedition will give us a better sense of the risk."
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