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G. DOWNSLOPE BERM WIDTH (Slope > 1%) <br /> 1. Slope: 2.0 If landslope is 1% or more, subtract rock layer width from <br /> adsorption width to obtain minimum downslope berm toe: <br /> 26.7 ft minus 10.0 ft rock = 17 Foot minimum adsorption area <br /> 2. Calculate minimum mound size: <br /> a. Determine depth of clean sand at upslope edge of rock layer: <br /> From Site Evaluation step C1: 18.0 inches clean sand <br /> b. Add depth of clean sand (2a) at upslope edge, plus 1 foot of rock plus 1 foot <br /> of cover to get mound height at upslope edge or rock layer. <br /> 18.0 in / 12 = 1.50 feet + 1ft + 1ft = 3.50 ft upslope height <br /> c. Enter table with landslope to get upisope berm multiplier of 3.70 <br /> d. Multiply berm multiplier 2c by upslope mound height 2b to get uplope berm width: <br /> 3.70 X 3.50 equals 13 feet upslope berm width <br /> e. Multiply rock layer width D2 by landslope to get drop in elevation- <br /> 10.00 <br /> levation:10.00 feet X 2.0 %slope = 20.00 / 100 = 0.20 feet <br /> f. Add depth of clean sand for slope difference 2e at downslope edge, to the <br /> mound height at the upslope edge of rock layer 2b to find downslope height: <br /> 3.50 feet + 0.20 feet = 3.70 feet downslope height <br /> g. Enter table with landslope and downslope berm multiplier of : 4.35 <br /> h. Multiply berm mult. by downslope mound height to get downslope berm width: <br /> 4.35 feet X 3.70 equals 16.1 feet downslope berm width <br /> i. Compare values of step G1 16.7 ft & G2h 16.1 ft <br /> The greater of the two values 47 is the downslope berm width <br /> j. Total mound width is the sum of upslope berm width G2d, plus rock layer width <br /> D2, plus downslope berm width G2i: <br /> 13.0 feet + 10.0 feet + 16.7 feet = 39.6 ft wide <br /> k. Total mound length is the sum of uplsope bermwidth G2d, plus rock layer length <br /> D3, plus upslope berm width G2d: <br /> 13.0 feet + 33.0 feet + 13.0 feet = 58.9 ft long <br /> i. FINAL MOUND DIMENSION 1S: 40 ft wide X 59 ft long <br /> % SLOPE DOWNSLOPE MULTIPLIER UPSLOPE MULTIPLIER <br /> 3 TO 1 4 TO 1 3 TO 1 4 TO 1 <br /> 3.00 4.00 3.00 4.00 <br /> 1.0 3.09 4.17 2.91 3.85 <br /> 2.0 3.19 4.35 2.83 3.70 <br /> 3.0 3.30 4.54 2.75 3.57 <br /> 4.0 3.41 4.76 2.68 3.45 <br /> 5.0 3.53 5.00 2.61 3.33 <br /> 6.0 3.66 5.26 2.54 3.23 <br /> 7.0 3.80 5.56 2.48 3.12 <br /> 8.0 3.95 5.88 2.42 3.03 <br /> 9.0 4.11 6.25 2.36 2.94 <br /> 10.0 4.29 6.67 2.31 2.86 <br /> 11.0 4.48 7.14 2.26 2.78 <br /> 12.0 1 4.69 7.69 2.21 2.70 <br />