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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 - 1.0 ft = 2.0 ft B. Calculate Upslope Height: Clean Sand Lift (4.A) +media depth (1 ft.) +cover (1 ft.) = Upslope Height 2.0 ft + 1.0 ft + 1.0 ft= 4.0 ft 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 (4.13) = Upslope Berm Width 3.33 1 x 4.0 ft = 1.0 ft E. Calculate Drop in Elevation Under Bed: Bed Width (2.13) X Land Slope (1.1)) + 100=Drop (ft) 10.0 x 5.0 % + 100= 0.5 ft F. Calculate Downslope Mound Height: Upslope Height (4.B) +Drop in Elevation (4.E) =Downslope Height 4.0 ft + 0.5 ft = 4.5 ft G Select Downslope Berm Multiplier 5.00 (figure D-34) (based on land slope): H. Calculate Downslope Berm Width:Multiplier (4.G)X Downslope Height (4.F) =Downslope Berm Width 5.00 x 4.5 ft = 22.5 ft I. Calculate Minimum Berm to Cover Absorption Area: Downslope Absorption Width (3.B or 3.C) +4 ft. =ft 17.0 ft + l--J ft = 21.0 ft J. Design Downslope Berm =greater of 4H and 41: 22.5 ft K. Select Endslope Berm Multiplier: 4.00 (usually 3.0 or 4.0) L. Calculate Endslope Berm (4.K)X Downslope Mound Height (4.F) =Endslope Berm Width 4.00 x 4.5 ft = 18.0 ft M. Calculate Mound Width: Upslope Berm Width(4.D) + Bed Width (2,6) +Downslope Berm Width (4.J) =ft 13.0 ft + 10.0 ft + 23.0 ft = 46.0 ft N. Calculate Mound Length: Endslope Berm Width (41) + Bed Length (2.C) +Endslope Berm Width (41) =ft 18.0 ft + 55.0 ft + 18.0 ft = 91.0 ft D-34:slope Muttiplier Table Land Slope`.K 0 1 2 3 4 1 5 1 6 1 7 8 9 1 10 1 11 i2 13 14 15 16 17 18 19 1 20 21 1 22 1 23 1 24 25 Upslope 3:1 3.00 2.91 2.83 2.75 2.68 2.61 2.54 2.48 2.42 2.36 239 2.26 2.21 2.17 2.13 2.09 2.06 2.03 2.00 1.97 1.95 1.93 1.91 1.89 1.87 1.85 Berm RaCiO 4:1 4.00 3.85 3.70 3.57 3.45 3.33 3.23 3.12 3.03 2.94 2.86 2.78 2.70 2.62 2.5512.481 2.41 12.35 12.29 12.23 12,18 12.13 12.0 2-03 1 1.98 11.93 Land Slop!% 0 1 2 3 4 1 5 1 6 1 7 1 8 1 9 1 10 1 11 1 12 1 13 1 14 1 15 1 16 1 17 1 18 1 19 1 20 21 22 23 24 25 Downslope 3:1 3.00 3.09 3.t9 3.30 3.41 3.53 3.66 3.80 3.95 4.11 4.29 4.48 4.69 4.95 5.24 5.55 5.88 16.24 16.63 17.04 17.47 17.93 1 8.42 18.93 19.46 10.02 Be1119 Ratio 4:1 4.00 4.17 4.35 4.54 4.76 5.00 5.26 5.56 5.88 6.25 6.67 7.14 7.69 8.29 8.92 9.57 10.24 10.94 11.67 12.12 13.19 13.99 14.82 15.67 16.54 17.44 5. ORGANIC LOADING: (Optional) A. Organic Loading = Design Flow X Estimated CBOD in mg/L in the effluent X 8.35 : 1,000,000 (See Table III) � Igpd X mg/L X 8.35 _ 1,000,000 = C�lbs CBOD/day B. Calculate System Organic Loading: lbs. CBOD (5.A) + Bed Area (2.A) = lbs/day/ft2 lbs/day + LJft2 = lbs/day/ft2 Table III (7083.4030) Treatment CBOD (mg/L) Level A 15 Level B 25 Level C 125