high-pressure water is required. From the 36-inch main -pressure line, 

 water is distributed to the surge well, hydraulic giants, eductors and 

 to the water-cooling system for the auxiliary equipment used with the 

 pumping activities. Branching off from the 36-inch main are two 28-inch 

 lines through which water is carried nearer to the sand -moving operation. 

 Branching off from the 28-inch lines are two 21-inch lines at each opera- 

 tional point, one as a pressure line to the hydraulic giant and one as a 

 pressure line to the sand eductor. To eliminate as much pipeline friction 

 as possible, the lines are as large in diameter as can be satisfactorily 

 handled in laying or moving from place to place. 



At each point of operation, which is usually from 75 to 200 feet from 

 the sandhill which is to be moved, are located the hydraulic giant and 

 eductor. The hydraulic giant ejects the water at high velocity and at a 

 pressure varying between 60 and 120 pounds per square inch onto the sand- 

 hill. The water dislodges the sand, and the suspended sand in water 

 flows downgrade, a distance of from 75 to 200 feet, on a slope which 

 creates enough turbulence to hold the sand material in suspension. At 

 the base of this slope is the eductor, which picks up the sand -water mix- 

 ture and starts its flow through a venturi and thence into a 21 -inch or 

 28-inch line which flows into the surge pit. A high-pressure water line 

 also enters into the eductor, and water is ejected through a nozzle at 

 65 to 125 pounds per square inch pressure, directly into the venturi and 

 acts, in a measure, as a force to carry the suspended material through 

 the pipe. The venturi thus creates a suction, also helping to carry 

 additional material through the discharge pipe. In most operational cases, 

 the discharge line has a negative slope, or a drop of from to 4 percent; 

 however, in some cases the line has had a positive slope of 5 percent. 

 The suspended material in the various discharge lines flows distances up 

 to 2,600 feet to reach the surge pit. All of these discharge lines enter 

 the surge pit, which is located on the slope directly in back and above 

 pump No. 3 in the pumphouse. 



The material in the surge pit flows into the surge well, which is a 

 rectangular steel box, divided into three sections, with a trash rack 

 surrounding it to prevent foreign material from entering the well. The 

 suspended material flows into this well through slide gates and then, by 

 gravity, down to the pumphouse via a 36-inch line to pump No. 3. If the 

 sand suspension is too heavy, additional water is added at the surge well 

 by a pipe coming from the 36-inch high-pressure line. Pump No. 3 draws 

 in the water at from 4 inches of vacuum to 2 pounds per square inch 

 pressure, and discharges the mixture into a 30-inch line at about 80 pounds 

 per square inch pressure. This line leads into pump No. 4, set at right 

 angles to pump No. 3 and 9 feet above it. The material is discharged from 

 pump No. 4 into a 28-inch line at about 155 pounds per square inch pressure. 

 This line extends about 11,200 feet along the beach on the same plane to 

 a booster station which has two additional 28-inch dredge pumps. These 

 pumps are so located that they can be operated individually or in series 

 with each other, dependent upon the length of the discharge line to the 

 point of depositing the material. At the booster station, the pressure 

 in the 28-inch discharge line from pump No. 4 has decreased to from. 2 to 



