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G. Downslope Berm Width 1. If the landslope is 1%or more, subtract the rock layer width from the absorption width to obtain minimum downslope berm toe: 27- 10 = 17 feet minimum downslone. 2. Calculate the minimum mound size: a. Determine the depth of clean fill at the upslope edge of the rock layer: (required seperation) 3' - 1.87' = 1.13 feet b. Add the depth of clean sand for 2a,the depth of the rock layer, and 1' for the topsoil cover needed to determine the mound height at the upslope edge of the rock layer; 1 + 1 +1.13 =3.13' c. Select the table multiplier for the upslope berm based on land slope against 4:1 berm slope. 3.23 d. Multiply the berm multiplier by the upslope mound height to determine the upslope width; 3.23x3.13 = 10feet e. Multiply the rock layer width by the landslope to determine the elevation drop; (lOx6)/ 100 =.6feet f. Add the depth 2e to 2b to determine the mound height at the downslope edge of the rock layer; .6 + 3.13 = 3.73 Feet g. Select the table multiplier for the downslope berm based on the land slope against 4:1 berm slope. 5.26 h Multiply the berm multiplier for the downslope mound height to determine the downslope width; Land Downslope upsiope 3.73 x 5.26 =20 feet slope berm multipliers berm multipliers i. Compare the values in G.1 �n% for given ratios for given ratios (17 feet) and step G.2h(20 feet). Select the greater of the two values 4:i s:1 4:1 5:t as the downslope berm width; 20 feet. 0 4.0o s.00 a.00 s.00 j. Total mound width is the sum 1 4.17 5.26 3.85 4J6 of G.2d, D.2 and G.2i; 10 + 10 + 20 =40 feet. 2 4.35 5.56 3.70 4.54 k. Total mound length is the sum 3 4.54 s.ss 3.5� 4.35 of G.2d, D.3, and G.2d ; 4 4.76 625 3.45 4.17 10 + 63 + 10=83 feet 5 5.00 6.67 3.33 4.00 6 5.26 7.14 3.23 3.85 Final Dimensions of the Mound 7 5.56 7.69 3.12 3.70 40 feet bv 83 feet 8 s.sg 8.33 3.03 3.57 9 6.25 9.09 2.94 3.45 10 6.67 10.00 2.86 3.33 11 7.14 11.11 2.78 3.23