Technical Issues: Jettisoning, Damage Stability, Refloating

An 80,000-DWT tanker is en route from Pajaritos, Mexico, to a refinery on the Delaware River with a cargo of 78,500 tons of Isthmus crude oil. The ship experiences a mechanical problem with its gyro compass and grounds in 35 feet of water near Diamond Shoal. The ship runs head-on into the shoal at 15 knots and comes to rest with 45 percent of her length resting on the sand. The hull remains intact and there are no leaks. A hurricane is approaching and will arrive within 16 hours. The increasing force of the winds and waves is expected to force the ship further onto the shoal, with eventual structural failure due to very high bending stresses. Internal transfer of the cargo will not refloat the vessel, and lightering is not possible due the deteriorating weather and distance from lightering resources. The discharge of 1,700 tons of cargo will allow the ship to refloat and continue its voyage. Delay will result in the ship being damaged beyond the point where she and her cargo can be saved.


This scenario was not used in the 1982 study and is included here to draw attention to the issue of jettisoning. While the incident unfolds on the East Coast, the scenario could apply to any coast or region.

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