An international survey (Michel et al., 2005) has identfied over 8,500 sunken shipwrecks in marine waters around the world, including more than 1,500 sunken tank vessels (≥ 150 gross tons) and nearly 7,000 sunken non-tank vessels (≥ 400 gross tons). These wrecks may contain as much as 20 million tons (140 million barrels) of oil and other hazardous materials. Sporadic or continuous leakages or potential sudden massive spillages from these wrecks, 75 percent of which stem from World War II, pose a continual risk across the globe. The problem of potentially-polluting wrecks has long been discussed and recent incidents around the world…