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downslope mound height, h_, will be 3*0 0.08 x 8.0 s 3.64 feet. From the <br />table on page 19 for a slope ratio of *1:1, the dike multiplier is 5.88. <br />This value multiplied by the downslope dike height of 3*64 gives th** value <br />of 21.4 feet for dp. The upslope dike multiplier is 3«03 for a slope ratio <br />of 4:1. Since the^upslope mound height is 3.0, the upslope dike width is <br />3.0 X 3.03 = 9.1 feet. <br />r <br />Note from page 13 with a 36” perforation spacing that a 1-1/2 inch lateral <br />cannot be used for a length of 62.5 feet, if the manifold is located on one <br />end. With an 8-foot wide rock bed, and the proposed revisions to Chapter 7080, <br />two perforated laterals could be used spaced 4 feet on centers. If the <br />perforations are spaced every 4 feet, there will be 15 lateral perforations <br />for each of the two laterals or a total of 30 perforations. From the <br />perforation discharge table on page 17, a 1/4 inch perforation at a <br />discharge pressure of 1.0 foot of head discharges 0.74 gpm. The 30 <br />perforations in this pressure distributivi* network will require a flow rate <br />of 22.2 gpm. Also, the center table on page 17 shows that 1-1/2 inch <br />diameter laterals can be used with 15 of the 1/4-inch perforations. <br />Pages 19 and 20 present a suggested design procedure using the basal width <br />concept. Pages 21 and 22 present information on the definition of basal <br />width and its importance in mound design as well as several examples on <br />calculating dike widths. <br />-vi- <br />i*ii» 11fi ■ ■