from the venturi opening. Water at from 65 to 125 pounds per square inch 

 pressure is jetted directly into the pipe opening, thus forcing the 

 material through the pipe. An eductor is considered to have a maximum 

 water efficiency of 30 percent in lifting; however, in the present 

 situation the efficiency is greatly increased as the necessary height to 

 which the water must be lifted is small, and after reaching the height 

 desired, the slope is then downgrade. This creates a certain amount of 

 suction, thus making for a greater efficiency in the system. The actual 

 water efficiency of these eductor systems is about 45 percent. The per- 

 centage by volume of suspended material being delivered to the surge pit 

 is 13.4 percent during the best operating conditions for which results 

 were obtained. The efficiency of an eductor is at a maximum when the 

 eductor is just covered with a solid mass of water. If the eductor were 

 to be used for subsurface operations, the efficiency would drop as the 

 head of water above the jet increased. It takes about 10 feet of head 

 to acquire 1.5 feet of lift in an eductor, thus indicating considerable 

 power loss and thus eliminating the use of the eductor except for special 

 operations. In the operations at the Hyperion project, the contractor 

 was able to use an eductor to force water through 3,600 feet of pipe with 

 a 4-foot drop in elevation, which indicates that material can be delivered 

 a long distance on nearly level ground with an eductor. At the Hyperion 

 project, for all grades under 4 percent, an eductor is in operation. For 

 grades of 4 percent or greater, a sluice pipe arrangement is used where 

 gravity flow carries the material to the. sump pit. However, to protect 

 the entrance to the sluice line from sanding up, a jet of water from a 

 2.5-inch line extending from the high -pressure line is set to discharge 

 directly into the intake opening of the sluice line. The efficiency or 

 the percent by volume of suspended material through the sluice line 

 during the best operating conditions noted was 21 percent, Eductors are 

 manufactured by Schutte § Koerting and by Joshua Hendy Iron Works. The 

 Hyperion project is using units of a design similar to the Schutte § 

 Koerting. 



Approximately 11,200 feet northward along the beach from the main 

 pumping station is located the booster station, which is a semipermanent 

 structure of sheet metal, with motors and pumps mounted on concrete bases. 

 In this station are two 28-inch pumps, one a Fort Peck and the other a 

 Meckum Engineering Company pump. Both are driven by General Electric 

 motors and both pumps and motors are of the same type as the pumps in the 

 main pumphouse. Due to the length of the pipes and the various frictions 

 developed, the pressure of the material in the line has dropped from 155 

 pounds per square inch to from 5 inches of vacuum to 15 pounds per square 

 inch pressure at the booster station. These pumps are installed and 

 connected so that both pumps can be bypassed, or either of the two pumps 

 can be used separately, or both pumps can be operated in series. When 

 one pump is in operation, the pressure is built up to from 80 to 90 pounds 

 per square inch. When both pumps are in operation, the pressure is 

 increased to 155 pounds per square inch, the number of pumps in operation 

 being dependent on the length of the discharge line and the amount of 

 material in suspension being delivered. The booster station also contains 

 auxiliary equipment for the efficient handling and operation of the pumps 



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