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3.5 - G. DOWNSLOPE BERM WIDTH Slope:- Cover l' ' ,� • / 1. If landslope is 1% or more, 1y S ., subtract rock layer width from adsorption width - 4.e •' :. •.. '. . ' to obtain minimum downslope berm toe C1eartSand f� r' '.:• 6'Topsoa r �2 Z ft - /o ft = feet NaturalSoa /'5 •- I Calculate Minimum mound Size a. Determine depth of clean sand fill at upslope Width Downslope wid upslope edge of rock layer: f Z Rock Width Absorption Width Separation T - IsS ft = /,, feet Jo b. Add depth of clean sand for separation (2a) at upslope edge, depth of rock layer (1 foot) to depth of cover (1 foot) to find the mound height at the upslope edge of rock layer; �- /.5 ft + ift + lft = 3•s feet C. Enter table with landslope and upslope berm upslope Width ratio. Select berm multiplier of -X,5- � shy,7,,p�e Widthopoo o°°n0,; Rock Bed r�°.�°n0 0�o UPS Upi pe Widt; "3"'••'t^ Width d. Multiply berm multiplier by upslope mound ' 9c•,o°.ov°qs °,QQ Qayp QCp�Op°A i. Len thp.• po Qoao - height to find upslope berm width: > � /��o� 17 � 3,S x 3,S = /Z•jfeet , e. Multiply rock layer width by � Downslope w;dth landslope to determine drop in elevation; - Absorptionwidth��r L_x U % . 100 = 0•c/ feet 1? � 17 f. Add depth of clean sand for slope Total Length difference (2e)at downslope edge, to 7S p the mound height at the upslope edge of rock layer (2b) to find the downslope height; 3.�;- ft -�cj Ly- ft = 3,feet g. Enter table with landslope and downslope berm ratio. Select berm multiplier of IV- F - h. Multiply berm multiplier by downslope mound height to get BERId SLOPE MULTIPLIERS downslope berm width: 3,5_x 'q, Y = �_feet Land DOWNSLOPE UPSLOPE i. G.117 SIO multipliers for various berm multipliers for various Compare the values of step iu 90 berm slope ratios berm slope radix+ and Step G.2h Select the greater of the two values as the 1: ° s 4 5.o 6.0 7.0 7' downslope berm width; feet 0 3.0 4.0 5.0 6.0 7.0 3.0 s. j. Total mound width is the sum of 1 3.09 4.17 5.26 6.38 7.53 2.91 3.85 4.76 5.66 6.54 2 3.19 4.35 5.56 6.82 8.14 2.83 3.70 4.54 5.36 6.14 t upslope berm (G-2d) 3 3.30 4. 5.88 7.32 8.86 2.75 3.57 4.35 5.08 5.79 width plus rock layer width (D.2) 4 3.416.2s 7.89 9.72 2.611 3.as 4.17 4.84 5.46 plus downslope berm width(G.21)- S 3.53 5.00 6.67 8.57 10.77 2.61 3.33 4.00 4.62 5.19 12 ft + I G ft + L�ft = qZ feet 6 3.66 5.26 7.14 9.38 12.07 2.51 3.23 3.85 4.41 4.93 1:. Total mound length is the suin of upslope 7 3.80 5.56 7.69 10.34 13.73 2.48 3.12 3.70 4.23 4.70 > berm width (G.2d) plus rock layer length (D.3) 8 3.95 5.88 8.33 11.54 15.91 2.42 3.03 3.57 4.05 4.49 ; 9 4.11 6.25 9.09 13.04 18.92 2.36 2.94 3.45 3.90 4.30 plus upslope berm width (G.2d) 10 4.29 6.67 10.00 15.00 23.33 2.31 2.86 3.33 3.75 4.12 4 ft + JL ft + 2- f: feet th7 s 11 4.45 7.14 11.11 17.65 30.43 2.26 2.78 3.23 3.6 I 3.95 �oYC r 12 4.69 7.69 12.50 21.43 43.75 2.21 2.70 3.12 3.49 3.80 4 Final Dim esions• ote:The product of the multiplier and the height results in the horizontal distance to where erm meets the original land slope.Example:Height at upper edge of rock layer is 3.0 feet, ayer is 10 feet wide,land slope is 6%and berm slope ratio is 4:I.Upslope berm width is 3.2 1 ? .0 G X C =9.7 ft:height at lower edge of rock layer is 3.0+10 x 0.6=3.6 ft and downslupe ben,,M s5.26x3.6=18.9 ft.