18,000 deadweight tons (DWT). (One DWT is roughly equivalent to 250 gal. 

 capacity). By 1956 it had increased to 45,000 DWT; by 1968 to 325,000 DWT; 

 and by 1972 to 476,000 DWT (Moestert 1976). Cy 1975 the world fleet had 

 540 ships over 200,000 DWT (Department of Transportation 1976); there are 

 undoubtedly more today. The size of these "supertankers" is almost incom- 

 prehensible. The largest is almost as long as the Empire State Building is 

 tall and has a draft when loaded of about 90 ft (27.4 m). 



Existing American ports cannot accommodate tankers of the 200,000 DWT 

 size and larger. East Coast ports are limited to tankers in the range of 

 70,000 to 80,000 DWT; although some larger tankers have been admitted when 

 only partially loaded (to reduce draft). Some West Coast ports have received 

 tankers of 125,000 DWT. 



The U.S. Government and the oil industry have been examining possibili- 

 ties of constructing ports to receive "supertankers." Two sites have been 

 approved for construction of offshore receiving facilities for larger tankers 

 and "super-tankers": Seadock off the coast of Texas, and LOOP off the 

 Mississippi Delta (Siler 1977). The receiving facilities will be 20 to 25 

 miles (32.2 to 40.2 km) off the coast in deep water and are expected to 

 receive oil from tankers as large as 325,000 DWT (Department of Transporta- 

 tion 1976). Tankers will use shipping routes that pass through the 

 Caribbean Islands or around the coast of Florida. 



The oil industry has argued that use of larger tankers will reduce 

 traffic, lower the number of accidents, and reduce the amount of oil spilled. 

 Data from 18 major tanker accidents, reported by the Smithsonian Institution 

 Center for Shortlived Phenomena, appear to support industry's contentions. 

 In these 18 major oil spills, the average amount of oil lost per DWT being 

 carried is less for ships over 80,000 DWT than for smaller ships (Table 1). 

 However, it appears from these data that the average size of major oil 

 spills from larger tankers is several times greater than major spills caused 

 by smaller tankers. This may indicate that if average tanker size increases, 

 there will be fewer accidents and a smaller percentage of oil spilled, but 

 if an accident does happen it is more likely to be serious. Remember, how- 

 ever, that small spills in sensitive areas may cause serious damage and that 

 a vessel need not be very large to cause a big oil spill. The Argo Merchant, 

 for example, was only 29,000 DWT yet spilled more than 7 million gal. 



I would like to turn now to several things which I believe the Service 

 should consider in planning for and responding to oil spills. Since 1970 

 the largest percentage of oil reported spilled each year, roughly 85 to 98 

 percent, has been from accidents of over 10,000 gal. Oil spills of 100,000 

 gal or more accounted for betv/een 55 and 87 percent (Table 2). Although 

 small spills may cause significant damage in critical areas, most spills 

 under 10,000 gal in coastal waters and under 1,000 gal in inland areas 

 probably will not warrant Fish and Wildlife Service involvement in cleanup 

 operations. In general, I believe the Service needs to pay greatest attention 

 to spills over 10,000 gal . 



Analysis of data on volume of pollutants spilled by month indicates peak 

 months for volume spilled are October, December, January, March, April, and 

 June. Between 2 and 4 million gal of pollutants (mostly oil) have been 



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