concrete fabricators prefer not to navigate a channel to reach their 

 deepwater construction site. 



The average required clearances for both the vertical and horizontal 

 dimensions in the access route from the fabrication yard to the open sea 

 are from 210 to 350 feet, depending, of course, on the size of the 

 platform and the required margin of safety [40]. Where bridges can be 

 opened, horizontal clearances should also be determined. Vertical 

 clearance requirements for gravity platforms are much greater than for 

 steel platforms. Since pillar and superstructure heights can exceed 400 

 feet, bridges of any kind are probably unacceptable [26]. 



The transportation of raw materials, personnel, fuels, stores, 

 equipment, and machinery and parts for a fabrication yard is likely to 

 require all four principal forms of transportation--air, road, rail, and 

 sea. The magnitude of traffic will vary with the type and number of 

 platforms under construction. The volume of raw materials required for 

 a cement gravity platform, for example, can be as much as ten times that 

 required for a steel platform. If a spur line is available or constructed, 

 a two-platform cement yard could require three train deliveries per day 

 for raw materials (aggregate, cement, steel). Also required would be 

 two rail tank cars per week for fuel and lubrication oils and one rail 

 car per week for machinery and spare parts [26]. 



If a source of raw materials is available near a waterfront site, 

 cement-platform yards would be likely to receive the materials by barge-- 

 an estimated two to three 3,000 ton barges would be required every two 

 weeks. Generally, because shipping is the least expensive transportation 

 alternative, fabricators will ship major materials to the yard if at all 

 possible. 



In contrast to the broad range of potential steel -jacket-platform 

 sites, the choice of a concrete-gravity-platform fabrication site is 

 largely dependent upon proximity to the drilling site. Concrete- 

 gravity-platforms are too heavy and massive to be towed long distances; 

 if they are to be used in Alaska, they will have to be constructed in 

 Alaska. 



Since platform-fabrication yards employ hundreds of skilled iron 

 workers and welders, a sponsor will attempt to locate in the vicinity of 

 a labor pool which has an abundance of these skills. Areas with existing 

 ship repair and construction yards have available welders and other 

 skilled craftsmen in the work forces. However, many of the skilled 

 workmen and management staff may be imported from existing Gulf Coast 

 fabrication yards, to provide a nucleus of personnel who know and under- 

 stand the fabrication business. In order to accommodate the total 

 workforce required (up to 1,200) a sponsor will also attempt to locate 

 near a community capable and desirous of accommodating industrial-based 

 growth. 



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