Risk Assessment Of Potentially Polluting Shipwrecks
This map highlights the many potentially polluting shipwrecks along U.S. coastlines.
Notes
The Montebello is located on California's Central Coast, near Morro Bay. The NOAA established a Remediation of Underwater Legacy Environmental Threats (RULET) Database to track and categorize shipwrecks, and areas of high priority and concern. ?A task force is evaluating the risk posed by a sunken oil tanker, the SS Montebello. It went to the bottom after being attacked by a Japanese submarine during World War II. State and federal officials want to know if the ship is still carrying its cargo of oil, and if that oil could escape.
Enlarge Chevron/UNOCAL The SS Montebello, shown in its glory days, was torpedoed by a Japanese submarine during World War II.
Chevron/UNOCALThe SS Montebello, shown in its glory days, was torpedoed by a Japanese submarine during World War II.
At stake is a coastline known for its stunning scenery and wildlife sanctuaries. The task force was put together a couple of years ago at the urging of state Sen. Sam Blakeslee.
"I actually was reading in my local weekly newspaper about this amazing history of a shipwreck that occurred off our coast and described the fact that there still may be 3 million gallons of oil down at the bottom of the ocean," Blakeslee says. "And no one in all these 70 years had really stepped up and said, 'It's our responsibility to understand what the threat is to the coast.' "
In fact, for most of the past 70 years, most people didn't even know the oil tanker was down there.
"I didn't even talk about it because I was called a liar," says 92-year-old Richard Quincy, the last surviving member of the crew of the Montebello.
Quincy says they knew the voyage would be dangerous, and took a vote on whether or not they wanted to go. But with the nation at war, "everyone had to give something."
Enlarge Robert Schwemmer/NOAA/USCG An unmanned ROV (remotely operated vehicle) is launched 900 feet underwater to study the wreckage of the SS Montebello.
Robert Schwemmer/NOAA/USCGAn unmanned ROV (remotely operated vehicle) is launched 900 feet underwater to study the wreckage of the SS Montebello.
On the morning of Dec. 23, just before dawn, Quincy was on watch when he saw the outline of a Japanese submarine in the water. Then came the torpedo.
"It was dark when we got hit," Quincy says. "It went so fast. It was hard to keep track of time. We were anxious to get off because we figured it was going to catch fire."
But the ship didn't catch fire because the torpedo struck the Montebello in front of the oil tanks. Everyone on the crew escaped in lifeboats, and the ship went to the bottom nearly intact, says Robert Schwemmer, a marine historian with the National Oceanic and Atmospheric Administration. He's seen the Montebello from a manned submersible twice, in 1996 and 2003.
"The ship looked like it just left the dock, except the fact that the upper wheel house is missing," Schwemmer says. "So we have 90 percent of the Montebello sitting there squarely on its keel. The question is: Is the oil on board?"
Schwemmer was on the Nanuq, the mother ship for the exploration of the Montebello. The Nanuq is owned by Global Diving & Salvage, and it sailed down from Seattle and basically parked above the sunken tanker. Onboard are unmanned remotely operated vehicles, or ROVs, that are being sent below to study the wreck. Schwemmer says they can do a better job than the manned submersibles.
Video of the dive on the Montebello.
"When you do a submersible survey, you are always moving," Schwemmer says. "The ROV allows us to actually come up to different locations, and stay on station, and study them in more detail."
And a detailed assessment of the threat posed by the Montebello is important to more than just California's coast. Kerry Walsh, a project manager with Global Diving & Salvage, says that's because the Montebello's not the only potentially polluting wreck that's been identified by the NOAA.
"This wreck represents the first one in many hundreds of wrecks that NOAA [is] looking at that are around the United States that have oil in them," Walsh says.
Enlarge Richard Quincy Collection Ordinary Seaman Richard Quincy, then 22, is seen aboard the SS Montebello. Quincy, now 92, is the last remaining survivor of the sinking of the SS Montebello.
Richard Quincy CollectionOrdinary Seaman Richard Quincy, then 22, is seen aboard the SS Montebello. Quincy, now 92, is the last remaining survivor of the sinking of the SS Montebello.
Those wrecks are strewn along both the East and West coasts, and the detailed examination of the Montebello could be a blueprint for evaluating them, says Walsh. There are a lot of steps in that evaluation. First, the ROV cleans portions of the Montebello's hull, then uses ultrasound to measure the thickness of the metal.
"Once that's done, then we bring in the nuclear tool, which is a diagnostic scan device, and we press that up against the hull, and we measure through the steel, and we can detect by the return signal from the neutron backscatter what's behind it," Walsh says.
You get one kind of signal if it was seawater and another kind of signal if it was oil, but they'll want to confirm those results. Walsh says Global Diving & Salvage is also taking samples from the cargo tanks with a tool they've invented that both drills into the tank and plugs the hole.
"And if that doesn't work, we have another device that's a magnetic patch that will seal it up forever," Walsh says.
And if it turns out that the Montebello is still carrying her cargo of crude, the biggest challenge of all may be figuring out how to protect the sensitive Central Coast from the threat lying 900 feet below the waves.
Source: http://www.npr.org/2011/10/18/141453907/oiafter-the-wreck-of-montebello?ft=1&f=1007
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