MARINE SALVAGE
Old Shipwrecks and
Cleaning up from the Past
By Greg Trauthwein
Oil mysteriously washes up on a pristine beach; the local news hounds flock; the maritime industry makes national news again ... but is it a new story? Marine salvage and subsea industry leaders gathered last month on the campus of the Maritime Institute of Technology and Graduate Studies (MITAGS) in Linthicum Heights, Md., to discuss the environmental, legal, financial and moral ramifications of the discovery and recovery of marine casualties, new and old, around the globe. Dubbed "Wrecks of the World: Hidden Risks of the Deep," the conference -- which was sponsored by a long list of marine industry organizations including the American Salvage Association, the Marine Technology Society, NAMEPA, the Maritime Law Association of the United States and the International Salvage Association, among others � focused on a number of critical issues surrounding the discovery and mitigation of
potential brewing ecological disasters. According to research by Dagmar Schmidt Etkin, PH.D., of Environmental Research Consulting (Cortlandt Manor, NY), there are approximately 8,500 identified large shipwrecks found in the world's oceans, representing between two and 15 million tons of oil and other hazardous materials. Of this 8,500, nearly 75% of the total, or 6,338, are World War II era wrecks, a total encompassing 1,065 tankers, 3,887 cargo ships and 1,416 military ships. The heaviest concentration of these wrecks are scattered in the South Pacific (2700) and North Atlantic (2200). "Over the years, many of us have had to deal with the effects of oil spills," said Clay Maitland, maritime attorney and founding chairman, NAMEPA. The assumption usually is that oil spills are from a current spill or illegal dump, whereas the truth is that some of them come from existing wrecks."
"This is a very complex issue, and we need a rational approach, from the technical to the legal to the finance, in educating the people regarding the importance of this issue," said Dr. Schmidt Etkin. "As part of the proactive approach, we need to step back and look at each of these 8,500 vessels, and using the tools we have on risk assessment, for example, and triage these vessels for prioritization. Perhaps a small percentage are the ones that will require a closer second look." The panels of experts from government, industry and academia agreed equally that while no two wrecks are alike, there are a common set of factors: water depth, local weather patterns, amount and types of hazardous materials found onboard, overall threat of environmental impact, and legal/political issues such as the handling of a vessel and human remains that may be deemed a "war grave"; that must be considered before considering action.
Chart 1
Range of Relative Costs for Oil Recovery (Average)
Relative Complexity Simple Impact Factors on Cost Shallow depth (<20m) Low viscosity oil � Protected water Local Mobiliztion Moderate depth (20-50 m) Moderate viscosity oil � Weather & sea restrictions � Regional mobilization Deep depth (50-250 m) High viscosity � Poor wreck condition Open water (limitations) � Long mobilization Extreme depths (>250 m) High viscosity � Poor wreck condition Open water (limitations) � Long mobilization Cost Range ($m) <1-5
While there are no shortage of interesting technologies and ideas when it comes to oil spill and shipwreck hazmat remediation, an interesting concept proposed by a European consortium headed by MARIN, the Maritime Research Institute Netherlands, is the Double Inverted Funnel for Intervention on Ship-wrecks-Project, or more simply, the DIFIS concept, which came to prominence in the wake of the Prestige disaster. The solution (pictured) relies on gravitational forces to channel the flow of leaking fuel towards the surface. Instead of channeling it directly to the surface, the fuel/water mix flow is channeled to a buffer reservoir/separator located 30 to 50 m below the sea surface.
(Photo Courtesy of MARIN www.marin.nl)
Moderate
2-7
Complex
5-20+
Highly Complex
20-100+
(Source: Global Marine Solutions B.V.)
Chart 2
Present: Examples of cargo/bunker removal
Vessel Name Alessandro Primo IevoliSun Year Country Quantity tonnes Cargo Water depth (m) 1991 Italy Dichlorethane/ Acrylonitrile 4000 Styrene/ bunkers bunkers Marine diesel bunkers Methanol/ bunkers 2000 <5000 Oil Heavy fuel Fuel Fuel 100-150 Fuel
110
2001
France
95 70
Osungno.3 IcePrince
1998 2009
Korea UK
160 350
60 65
Haven BowMariner
2008 2004
Italy USA
80 630
Solar1 Tanio(bow)
2006 1980
Philippines UK/France
90 100-130 70 150
Erika Yuilno.1 SeaDiamond
1999 1998 2007
UK/France Korea Greece
11,100
(Source: Global Marine Solutions B.V.)
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