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3. ABSORPTION AREA SIZING Note:Mound setbacks are measured from the Absorption Area. A. Calculate Absorption Width:Bed Width (2.B)X Mound Absorption Ratio (1.17)=Absorption Width 10.0 ft x 2.0 = 20.0 ft B. For slopes>1%,the Absorption Width is measured downhill from the upslope edge of the Bed. Calculate Downslope Absorption Width:Absorption Width (3.A)-Bed Width (2.6)=ft 20.0 ft - 10.0 ft = 00.07 ft 4. MOUND SIZING A. Calculate Clean Sand Lift: 3 feet minus Depth to Limiting Condition (1.C)=Clean Sand Lift (1 ft minimum) 3.0 ft - 1.2 ft = 1.8 ft Design Sand Lift(optional): 1.8 B. Calculate Upslope Height:Clean Sand Lift (4.A)+media depth (1 ft.)+cover (1 ft.)=Upslope Height 1.8 ft 1.0 ft 1.0 ft= 3.8 ft 0.14:5b[r Multiplier Table Land Slope 7 0 I 1 2 3 4 5 5 7 1 8 1 9 1 10 111 11 1 iJ 1 14 1 li f 15 1 17 1 IB 1 19 1 20 1 21 1 22 2T'124 1 25 ' Up310Fe 3:1 mowc 1.412 51 2.541'.46 2.41 2.3612.31j1.26 2.i1 t.:7�2.'311i.09 LG5 1.03 LK I I.i? I.i5 Lia Li! 1.19 1,87 1.85 84rfl Ra;ii- 14.1 J.00 3.85 3.70f 3,57 3.J5 3.3J-3.23;3.12 3.03,1.44 2.56 2.18 2,10 1.52 2.55 2,46 1.41 2.35 2.29 1.23 1.18 LU 2.05 2.03 1.98 L'r3 Land Slope a 0 I 2 3 d 5 1 6 7 8 9 j ul I l l 12 13 14 15 16 11 1 l8 19 20 21 21 23 24 1 25 (0lmslc10e 113:1 7.IX 7.C9 7.?, 3.3. 3.41 3.57 3.66 7.50 3.;5'4.11 4.29 4.:,? 4.69-,95!5.24 5.55 S.aB 6.2= 6.67 ?.04 7.A 7.il 3.42 8.93 9.46 1002 Bern Rano i41 J.00..174.35 4.54 4:16 5.00 5.26 5.56 5.8a 6.25 6.67 7.14 7.69 8.19,8.92 9.57 10,24110,94111:67112.42 :3.13 !3.9911412115,67 ;6.5411T,14 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 (4.6)=Upslope Berm Width 3.33 ft x 3.8 ft = 13.0�ft E. Calculate Drop in Elevation Under Bed:Bed Width (2.13) X Land Slope (1.D):100=Drop (ft) 10.0 ft X 4.0 % loo = C 0.40 ft F. Calculate Downslope Mound Height:Upslope Height (4.8)+Drop in Elevation (4.E)=Downslope Hei,;ht 3.8 ft + 0.40 ft = 4.2 ft G Select Downslope Berm Multiplier (based on land slope): 4.76 (figure D-34) H. Calculate Downslope Berm Width:Multiplier (4.G)X Downslope Height (4.F)-Downslope Berm Width 4.76 x 4.2 ft = F 20.0 -]ft I. Calculate Minimum Berm to Cover Absorption Area:Downslope Absorption Width (3.B or 3.C)+4 ft. =ft 10.0 ft + �� ft 14.0 7 f J. Design Downslope Berm =greater of 4H and 41: 20.0 ft K. Select Endslope Berm Multiplier: 3.00 (usually 3.0 or 4.0) L. Calculate Endslope Berm (4.K)X Downslope Mound Height (4.17)=Endslope Berm Width 3.00 ft x 4.2 ft = 13.0 ft M.Calculate Mound Width: Upslope Berm Width(4.D)+Bed Width (2.6)+Downslope Berm Width (4.J)=z ft 13.0 ft + 10.0 ft + 20.0 ft = 43.0 ft N. Calculate Mound Length:Endslope Berm Width (4.1.)+Bed Length (2.C)+Endslope Berm Width (4.L) =ft 13.0 ft + 63.0 ft + 13.0 ft = 89.0 ft Comments-