Summary of Working Paper No. 115-1998

I.5.4 “Oil Spilling from a Grounded Mid-deck Tanker”

By H. Tamama, Ship & Ocean Foundation, Tokyo, Japan

The changes in the scale of oil operations still stem from an ever increasing demand for energy. Import of natural energy resources has been vital to Japan and Far East Asian countries. One of the possible major commodities via the NSR in future would then be crude oil and natural gas, in particular along the eastern half of the route to these countries. Operations of tankers and LNG carriers along the NSR has undoubtedly a latent possibility of increasing marine pollution. Petroleum oil is one of the most widespread pollutants in the marine environment. Although there have been remarkable improvements in the case of vessel-source pollution, the increased number of ships and the rising tonnage of oil carried is still threatening to cause disastrous oil pollution. After the Exxon Valdez accident, regulations demanded considerable improvements in structure design of tankers.

Mid-deck tanker concept has then been developed in Japan as an alternative to the double hull design to meet the requirements of OPA 90 and IMO. The mid-deck tanker will have a significant potential in operations via the NSR. The basic features of oil spill caused by grounding of a typical mid-deck tanker were studied by the model tests at a large circulation channel in the SOF Technical Institute and the pollution prevention capability was discussed.