Double Wrapped

This article discusses that a probabilistic study showed that the use of double-hulled shuttle tankers could reduce the probability of spillage resulting from collisions, contact with non-ship objects, and groundings by 75 percent. American petroleum companies are already using double-hulled tankers. The efficacy of double-hulled vessels in preventing environmental threats was borne out in October 1997 by Conoco Inc.’s tanker Guardian. Conoco, based in Houston, has operated a 100 percent double-hulled U.S. tanker fleet since August 1998. Indeed, the company decided to build only double-hulled tankers months before Congress passed OPA 1990. Two new craft will join Conoco’s flotilla of four twin-hulled vessels in 1999. Conoco engineers met a number of challenges when they embarked on building a double-hulled fleet. Double-hulled vessels are inherently more expensive than single-hulled vessels. Maritrans Operating Partners LP, a wholly owned subsidiary of Maritrans Inc. in Philadelphia, operator and owner of one of the nation’s largest fleets of oil tankers, tugboats, and oceangoing petroleum tank barges, found a way to reduce those costs, which may serve as a model for other shipping firms. The 65-year-old company converted a two-decade-old single-hulled tank barge into a double-hulled vessel.