The deployment and emplacement of the 10-mile, three-conductor, 

 15-kv power cable from a shore-based power source to a load module on the 

 ocean floor involve many factors, such as bottom conditions, depths, and 

 tide and current data, which have an effect on the type and size of the cable 

 ship required. An intermediate landing craft was selected as an excellent 

 vessel for an emplacement of the 10-mile cable. 



The diameter of the cable is approximately 3 inches and the weight 

 of the cable is estimated at 7 lb/ft. The cable would be furnished in one 

 continuous length, with a termination and connector on the load module 

 end. The shore end would be capped and sealed. The cable would be loaded 

 at the manufacturer's plant and the cable ship dispatched to the emplacement 

 location. 



It is assumed that the load module would be transported and lowered 

 from a separate vessel. Therefore, at arrival on site the cable ship would float 

 the cable end on the surface (using inflatable floats and a towing craft) to the 

 module-carrying vessel. The cable would then be hoisted on board and the 

 necessary electrical connections made. 



The load module would then be placed overboard and lowered to the 

 bottom, with the cable ship paying out cable and standing well clear of the 

 module-lowering vessel. When the module is on the bottom, the lowering 

 line is slipped and retrieved and the cable ship then proceeds to the shore 

 landing, paying out cable en route. This general principle is utilized in.either 

 shallow or deep water. 



The method of landing the shore end may vary somewhat, depending 

 upon the nature of the site. If possible, the landing craft can work well into 

 shallow water. When beached, or nearly so, the cable ship floats the shore 

 end into the site. If the slope of the landing area is steep enough, the ship 

 may be able to beach out near the waterline. In this instance, a bight, or 

 the end can be passed ashore. Once the cable is ashore, it is led to the termi- 

 nal box, cut, and anchored in place. Trenching is recommended in surf and 

 beach areas for protection of the cable. For installing a 50-mile length of 

 power cable, the general procedure would be as noted above. The only major 

 change would be utilizing a larger ship, such as a landing ship tank, to 

 adequately cope with the increased weight of cable involved. 



A major-milestone chart and budget cost estimates for the 300-kw, 

 50-mile, shore-based power system are presented in Figure A-21. Costs for 

 transportation, deployment, property acquisition, site preparation, and 

 development programs were not included in the estimates. 



Worst-case conditions were assumed for the preliminary design of the 

 shore-based power system. The availability of electrical power at the shore 

 site would, of course, reduce budget costs for this system. 



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