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ABSORPTION AREA SIZING Note: Mound setbacks are measured from the Absorption Area. A. Calculate Absorption Width: Bed Width (2.8) X Mound Absorption Ratio (1.F) - Absorption Width 10.0 ft x 2.0 - 20.0 ft B. For slopes >I%, the Absorption Width is measured downhill from the upslope edge of the Bed. Calculate Downslope Absorption width: Absorption Width (3.A) - Bed Width (2.B) - ft 20.0 ft 10.0 ft MOUND SIZING A. Calculate Clean Sand Uft: 3 feet minus Depth to Limiting Condition (1.C) - Clean Sand Lift (1 ft minimum) 3.0 ft 1.7 ft - 1.3 ft Design Sand Lit (optional): 1.3 B. Calculate Upslope Height: Clean Sand Lift (4.A) + media depth 0 ft.) + cover (1 ft.) - Upslope Height 1.3 ft 1.0 ft+ 1.0 ft. 3.3 ft D•34: Slw Multiplier Table Und Slope % 0 1 1 3 4 5 6 7 8 9 to t i 12 13 14 15 16 11 l8 19 20 21 22 23 24 25 Upslwe 3:1 3.00 2.91 2.83 I.75 2.68 2.61 2.54 2.48 2,42.2,362,31J21612-2112,17 2.13 2.09 2.06 2.03 2.00 1.97 1.95 1.93 t.9t 1.89 124 12 5 Bert Ratto 4;1 4.00 3.85 3.70 3.51 3.45 3.33 3.23 3.12 3.03 2.94 2.86 2.78 2.70 2.62 2.55 2.48 2.41 2.35 2.29 2.23 2.18 2.13 1.08 2.03 11.98 11.93 Lind Slope % o I 1 1 1 3 14 5 6 1 8 9 110 1 11 -11T13 F14 15 16 17 1 1E 1 19 20 1 Zt I 22 23 24 25 Go1m51ope J:1 1.00 3.04 3.19 3.30 3.41 3.53 3.66 3.E0 3.95 4.11 4.29 4.48 4.64 4.95 5.24 5.55 5.8E 624 6.63 1.04 1,4I 7.43 8.42 Eig t0.D2 Belni Ratio 4:1 4.00.1.17 4.35 4.54 4.76 5.00 526 5.56 5.8E 6.25 6.67 7.14 1.69 8.29 E.91 957 1024 1094 11.67 12.42 13.19 13.49 14.82 17.44 C. Select Upslope Berm Multiplier (based on land slope): 3.33 (figure D-34) D. Calculate Upslope Berm Width: Multiplier (4.C) X Upslope Mound Height (4.11) - Upslope Berm Width 3.33 ft x 3.3 ft - 11.0 ft E. Calculate Drop in Elevation Under Bed: Bed Width (2.6) X Lara! Slope (1.D) + 100 - Drop (ft) 10.0 ft x 5.0 % + 100 = 0.50 ft F. Calculate Downslope Mound Height: Upslope Height (4.6) + Drop in Elevation (4.E) - Downslope Height 3.3 ft + 0.50 ft = 3.8 ft G. Select Downslope Berm Multiplier (based on land slope): 1 5.00 (figure 0-34) H. Calculate Downslope Berm Width: Multiplier (4.G) X Downslope Height (4.F) - Downslope Berm Width 5.00 x 3.8 ft 19.0 ft 1. Calculate Minimum Berm to Cover Absorption Area: Downslope Absorption Width (3.6 or 3.C) + 4 ft. - ft 10.0 ft 4 ft - 14.0 ft J. Design Downslope Bean - greater of 4H and 41: 19.0 ft K. Select Endslope Berm Multiplier: 1 3.00 (usually 3.0 or 4.0) L. Calculate Endslope Berm (4.K) X Downslope Mound Height (4.F) - Endslope Berm Width 3.00 ft x 3.8 ft M. Calculate Mound Width: Upslope Berm Width (4.D) + Bed Width (2.B) + Downslope Berm Width (4.J) - ft 11.0 ft + 1 10.0 ft + 19.0 ft - F 40.0 ft N. Calculate Mound Length: Endslope Berm Width (4.L) + Bed Length (2.C) + Endslope Berm Width (4.1.) - ft 12.0 ft + 38.0 ft + 12.0 ft F 62.0 ft Comments: