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and Wells, 1986, Fletcher G. Driscoll, Ed). Site - specific aquifer test data would need to be evaluated to refine this <br />estimate of hydraulic conductivity. A typical detail for the infiltration gallery is shown in Figure 3. Additional <br />investigation and analysis is recommended prior to finalizing design of this facility. <br />Pipeline lengths for conveying water from the pumping facilities to the recharge ponds were estimated from Plate <br />1. Pipeline diameters were estimated based on maintaining flow velocities below about 6 feet per second. <br />Conveyance pipe envisioned for use in the expansion is similar to that used in the initial phases of construction. <br />The PVC pipe, known as pressure irrigation pipe (PIP) is furnished with bell- and - spigot ends, and a sealing <br />gasket. Thrust blocks are required at pipeline bends and intersections. No independent restraining system is <br />employed. The pipe is supplied in 50 and 80 pounds per square inch pressure classes. The estimated pipeline <br />requirements associated with each of the recharge pond complexes are summarize in Table 1. <br />Water will also be delivered to recharge facilities located on the southeast side of Interstate 76 (see Plate 1). In the <br />case of Pond Complex 4, water will be conveyed through a 24 -inch pipe suspended within a 36 -inch steel <br />encasement that has been jacked and bored beneath the four -lane divided highway. In the case of Pond Complex <br />7, conveyance pipe will be installed within the interstate underpass. Reconstruction of this portion of the road is <br />scheduled to begin within the next year or two. Pipeline installation will need to be coordinated with road <br />improvements. <br />Water to be delivered to Pond Complex 7 will be conveyed through a lift station and clear well located on the east <br />side of Pond Complex 6. Three wells, each delivering approximately 1,500 gpm would deliver water to the lift <br />station for re- pumping through an 18 -inch diameter pipe to Pond Complex 7. The lift station would be designed to <br />deliver up to 4,500 gpm. The station will be required pump against a total head of about 140 feet, including a lift <br />of about 100 feet, and head losses totaling about 40 feet. The horsepower required at the station was estimated as <br />follows: <br />HP = (GPM) (H)/[(3960) (PE)], <br />Where HP = required horsepower, GPM = the pumping rate in gallons per minute, H = total head <br />in feet, and PE = pump efficiency, taken here to be 0.80 (Groundwater and Wells, 1986, Fletcher <br />G. Driscoll, Ed). <br />It is estimated that a 200 horsepower motor will be required at this location. A typical detail for the lift station is <br />shown in Figure 4. The lift station would be constructed of pre -cast, reinforced concrete rings, installed to a depth <br />of about 20 feet. An alternative to the lift station, involving pumping to Pond Complex 7 through a closed pipeline <br />system, was also considered. However, it was determined that the pressures associated with elevation gain, <br />hydraulic losses in the pipe, and the pressure surges during startup would exceed the rated capacity of pipe <br />already in place. Accordingly, this alternative was rejected. <br />Photographs showing typical constructed facilities at the TRSWA (well head, instrumentation details, rip -rap, and <br />power distribution) and PESWA (riser for test infiltration gallery) are shown in Figure 5. <br />- 4 - 130VL E <br />