hazard levels, and bulkheading and backfilling. Therefore, during site 

 development large volumes of fill materials may be dredged or trucked in 

 and the wetlands and littoral zones may be obliterated by bulkheads. 



Subproject: Roadways and Bridges (SP-8) 



Disturbing Activity: Roadway design 



Large quantities of materials are handled by a service base to 

 support exploratory and development drilling, production, and workover. 

 Roadway and railroad access are essential siting considerations. Repair 

 yards also may generate extensive shipments. The large volume of supply 

 traffic and the use of heavyweight trucks may require new access roads, 

 upgrading of old roads or a new rail link. Table 10 lists the quantities 

 of materials handled by a service base to supply an offshore rig that 

 drills four 15,000-foot wells per year. 



Table 10. Estimated Quantities of Materials Needed 

 for a Rig that Drills Four, 15,000-foot Wells per 

 Year (Source: Reference 1) 



Item 



Quantity per Rig Year 



Mud 



Cement 



Fresh water 



Drill pipe, casing and tubing 



Fuel for drilling 



2,568 tons 

 1,260 tons 

 5,200,000 gallons 

 1 ,820 tons 

 13,272 barrels 



3.5 PLATFORM FABRICATION YARDS 



3.5.1 Profile 



Offshore platforms that support oil and gas drilling and production 

 operations may be constructed of either steel or concrete. Steel plat- 

 forms are discussed in this section because they are the only type 

 currently constructed and in use on the United States OCS. Some of the 

 larger platforms being installed today in deep waters use 20,000 to 

 50.000 tons of steel (the Eiffel Tower is 7,000 tons of steel). The 



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