U-864 is to be raised

On 29 January the Norwegian Government decided that the wreck of German submarine U 864 is to be raised and the polluted seabed covered by a layer of clean sand and gravel. In 2007 and 2008, the Norwegian Coastal Administration (NCA), assisted by Det Norske Veritas, a private company on technical evaluations and risk assessments, undertook a more detailed study of the feasibility of raising the wreck with its cargo of mercury, and compared this measure against that of covering both the wreck and the contaminated seabed. “This work has identified the different risk factors in the two options. The decision of raising U-864 is the result of an overall evaluation; key aspects in this regard are the identified risks and the concerns that the coastal population and the fishing industry have over a capping  of the wreck”, says Minister of Fisheries and Coastal Affairs, Helga Pedersen.

On 10 November last year, the Minister of Fisheries and Coastal Affairs received the NCA’s technical assessment with the recommendation of capping both the wreck and the contaminated seabed. At the press conference Det Norske Veritas (DNV) presented its technical evaluation and risk assessment of the various factors that might impact the execution of alternative means of preventing further pollution from the wreck.

It was assessed that the raising of the wreck would probably remove much of the source of the pollution. If successfully achieved, the scheme that has been elaborated for the raising of the wreck will provide a satisfactory solution to the environmental challenges. The contaminated seabed is to be covered with clean sand and gravel, since such a large volume of contaminated sediments cannot be removed without spreading the mercury to new areas.

“The NCA’s and DNV’s thorough work has contributed to identifying different risk factors of the two alternative means of dealing with the pollution from the wreck and the contaminated seabed. I have found it extremely important to supplement these technical reports with discussions with the local population and politicians. Taking into account the major concerns of the coastal population and the fishing industry regarding the impact of permanently leaving this environmentally hazardous cargo on the seabed, we consider that raising the wreck presents an acceptable risk”, says the Minister of Fisheries and Coastal Affairs.

The NCA concludes that raising the sections of the wreck will be a technically feasible but highly complex operation. As part of its work during 2007 and 2008 on a detailed assessment of the raising of the wreck, the NCA conducted an EEA-wide tendering competition and negotiated a contract with a world-leading salvage company which has a long track record of completing challenging salvage operations, including raising of wrecks. The decision is subject to the consent of the Storting, the Norwegian Parliament. An independent external quality-assurance of the contract proposition and costs is also to be carried out in order to provide the best possible basis for a parliamentary decision.

The method now chosen for the raising of the wreck includes a number of risk-mitigating measures not present in previous proposals. “The wreck will be raised with a large container underneath it that will catch loose mercury, and it will be brought ashore in a special vessel. These are important measure, which in the scheme of things increases the likelihood of success”, says the Minister of Fisheries and Coastal Affairs, Helga Pedersen.