Van Oord completes unique Norwegian projectProjects and Operations // July 7, 2016
Van Oord has successfully stabilised the wreck of a World War II submarine off the coast of Norway. The Norwegian Coastal Administration awarded the contract to Van Oord at the end of 2015. The wreck, containing toxic mercury, was located at the top of a steep slope in the seabed. This slope was stabilised to guarantee the stability of the wreck. Van Oord deployed its flexible fallpipe vessel Stornes to undertake the project.
At a working depth of 150m, Van Oord built a foundation (counter fill) of 30,000 tonnes of sand and 160,000 tonnes of stone so that stability of the slope was guaranteed and the bow and surrounding sediments would not slide off the slope.
Preventing the spread of mercury to the environment was the main objective during the installation of the counter fill. Van Oord developed a special installation method for the placement of the sand to minimise the disturbance of the seabed. The Norwegian Institute for Water Research was subcontracted to monitor the project.