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,G. DOWNSLOPE BERM WIDTH 510 - cover 1• 1. If landslope is 1% or more, subtract rock layer width from adsorption width � - • � to obtain minimum downslope berm toe • Clean Sana D u 6'Topsoil s?Ll ft - 10 ft = 1 T feet Natural Soil 'r- 2. Calculate Minimum mound Size a. Determine depth of clean sand fill at Upslopes Width D wwryslope Width upslope edge of rock layer: Rocroidth Absor n Width Separation 3' - .Z ft = I feet 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; I ft + lft + lft = 3 feet c. Enter table with landslope and upslope berm Upspe Width ratio. Select berm multiplier of ?, qp aao o �w ...,sa o • ':;Up io a Width: . oo e. osb„�Rock BedV ?a d¢s0 oo sC Ups! ps o e Width ib . 1 J;pavaiaily d. Multiply berm multiplier by upslope mound o;SI(3" Width )2. . LA:as .a. Lente 3g height to find upslope berm width: r•� °•o6,p poa=av=°er°•a°ar .Z, 7 x 3 = g feet e. Multiply rock layer width by 1° Downslope Width3 - I landslope to determine drop in elevation; • Absorption Width /'i - /0 x /2, % s- 100 = It 2 feet i,: f. Add depth of clean sand for slope Total Lend, 7Z difference (2e)at downslope edge, to the mound height at the upslope edge of rock layer (2d) to find the downslope height; J, 2 ft + 3 ft = 9,,2 feet g. Enter table with landslope and downslope berm ratio. Select berm multiplier of '7. 6 7 h. Multiply berm multiplier by downslope mound height to get BERM SLOPE MULTIPLIERS downslope berm width: 7.&Tx Y.-Z = .33 feet Land DOWNSLOPE UPSLOPE i. Com are the values of ste G.1 i q Slope. berm multipliers for various berm multipliers for various P P in 9. berm slope ratios berm slope ratios and Step G.2h 33 Select the greater of the two values as the 3:1 4:1 5:1 6:1 7:1 3:1 4:1 5:1 611 7:1 8:1 downslope berm width; S3 feet 0 3.0 4.0 5.0 6.0 7.0 3.0 4.0 5.0 6.0 7.0 8.0 j. Total mound width is the sum of ' 3.09 4.17 5.26 6.38 7.53 2.91 3.85 4.76 5.66 6.54 7 41 upslope berm (G.2d) 2 3.19 4.35 5.56 6.82 8.14 2.83 3.70 4.54 5.36 6.14 6.90 3 3.30 4.54 5.88 7.32 8.86 2.75 3.57 4.35 5.08 5.79 6.45 width plus rock layer width (D.2) 4 3.41 4.76 6.25 7.89 9.72 2.68 3.45 4.17 4.84 5.46 ,.U6 plus downslope berm width(G.2i); 5 3.53 5.00 6.67 8.57 10.77 2.61 3.33 4.00 4.62 5.19 5.71 ft + I 0 , ft + 3 3 ft = 51 feet 6 3.66 5.26 7.14 9.38 12.07 2.54 3.23 3.85 4.41 4.93 5.41 k. Total mound length is the sum of upslope 7 3.80 5.56 7.69 10.34 13.73 2.48 3.12 3.70 4.23 4.70 5.1; 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 4 sx plus upslope berm width (G.2d); 9 4.11 6.25 9.09 13.04 18.92 2.36 2.94 3.45 3.90 4.30 4 6: /X- ft + 3 ft + )7, ft = fP?, feet 10 4.29 6.67 10.00 15.00 23.33 2.31 2.86 3.33 3.75 4 12 444 11 4.48 7.14 11.11 17.65 30.43 2.26 2.78 3.23 3.61 3.95 4 26 12 4.69 7.69 12.50 21.43 43.75 2.21 2. 0 3.12 3.49 3.80 4 t4 Final Dimesions: Note:The product of the multiplier and the height results in the honzontal distance to where the berm meets the original land slope.Example:Height at upper edge of rock layer is 3.0 leer.rock // layer is 10 feet wide.land slope is 6%and berm slope ratio is 4:1.Upslope berm width is 3.23 e t e X ,� ' 3.0.9.7 ft:height at lower edge of rock layer is 3.0+10 x 0.6=3.6 ft and downslope berm width 1s5.26x3.6w 18.9 ft.