Evidently this U-boat does have mercury.
Experts recommend encasing WWII submarine that sank off Norway
The Associated PressPublished: December 19, 2006
OSLO, Norway: The wreck of a World War II German submarine in waters off Norway's coast should be covered with sand to contain its cargo of environmentally damaging mercury, a study said Tuesday.
The submarine U-864 was torpedoed and sunk by the British submarine Venturer off western Norway on Feb. 9, 1945. Its wreckage, found by the Royal Norwegian Navy in March 2003, is believed to have 65 tons (about 70 U.S. tons) of mercury aboard.
The submarine was sunk while attempting to get to Japan, a German ally, with mercury for weapons production.
Studies revealed high levels of mercury around the wreck, which lies in 150 meters (500 feet) of water four kilometers (2.5 miles) off the western Norway island of Fedje.
In a report Tuesday, the Norwegian coastal administration recommended encasing the submarine in special sand, with a reinforced upper layer to prevent corrosion.
"Worldwide, about 30 large-scale encasing and coverage operations of mercury contaminated debris have been performed in the past 20 years," said the report. It said the measures were proven and provided permanent environmental protection.
If absorbed by fish, mercury can be passed on to humans in food, possibly harming their health.