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3. ABSORPTION AREA SIZING Note:Mound setbacks are measured from tlie Absorption Area. A. Calculate Absorption Width:Bed Width (2.E3)X Mound Absorption Ratio (t.F)=Absorption Width C10.0 ft X 2.0 = 20.0 ft B. For slopes>1%,the Absorption Width is me.asured downhilt from the upslope edge of the Bed. Calculate Downstope Absorption Width:Ab:�orption Width (3.A)-Bed Width (2.B)=ft C 20.0 ft - 10.0 ft = 10.0 ft 4• MOUND SIZING A. Calculate Clean Sand Lift: 3 feet minus Depth to Limitinq Condition (1.C)=Cleon Sand Lift (t ft minimum) 3.0 ft - 2.3 ft = 1.0 ft Design Sand Lift(optionat): ��1.0 B. CalCulate Upslope Neight:C(ean Sond Lift (4.A)+media depth (1 ft.)+cover (1 ft.}=Upslope Height 1.0 ft + 1.0 ft + 1.0 ft= 3.0 ft D-3.:�Idpe u,uRioiitr Table j Land Slope�� 4 ; 2 i 4 5 6 7 8 9 t0 l I i1 13� la i5 Ib i7 i8 I9 20 2i 22 13 24 25 i IJ�}j(n�o j3:i ;.iM: L91,"1$? 2d5 [.5$j2.51�2.1� ?.40 2.�2 i.?4�:.31�2.2b�?.24;t.'7�2.13�2.�4 2U5 i.l7i 2.�' i.y? LSi 1.53 1.9; I.F4 1.�7� LBi I I E�fiu kd.;0 �d:i a.ttkkt 3.85 3.70 3,5i 3.a5 3.33�'.13 ?.12 J.U3 2.5d 2.86 ?.7B iJ0 2,62 2.55 L�8 2.41 2.35 2.t9 2.2i 2.IB t.t3 2.08 1.G's 1.48 t.5i i I Land Slope`�� 7 i 2 3 4 5 h 7 8 9 j i�); i i , i2� i3 ia 15 i6 17 I8 t9 20 2l 22 t3 24 25 's j ��v;:f151r,Du �1:1 i.G� 3-4ilt.si ;;p 3.1I 's5? i.ES 3.fC 3.35-I.It�.i.29�;.;3 :.!+4 :.y5 5.ia�5.95 5.83 6.?1 E.Si i.i,4 ?.a? ?.Yl 8.�2 F.9i 9..15 ?�.0� � ��If�'i Rd;i� Id:t d.0(}�1.17i.1.35 4.54 lJ6 5.00 5.26 5.56 S.Bd 6.25 6.61 1.IJ 7.5i 8.'t9 8.92 9.57 10.td 10.5� 1L6? 12.J2 13.I9 13.44 !�1.82 )5.61 16.5; 17.�l.' Select Ups(ope Berm Mu(tiplier �' (based on land slope): 2.70 (figure D-34) D. Catculate Upslope Berm Width:Multip(ier (4.C)X Ups(ope Mound Height (4.6)=Ups(ope Berm Width 2.70 fc x 3.0 ft = 10.0 tt E. Calculate Drop in E(evation Under Bed:8ed Width (2.6) X Land Slope (1.D):100=Drop (ft) 10.0 ft X 12.0 % : 100= 1.20 ft F. Calculate Downslope Mound Height:Upslope Height (4.6)+Drop in E(evation (4.E)=Downslope Height 3.0 ft + 1.20 ft = 4.2 ft � Select Downs(ope Berm Mu(tiplier (based on land slope): 4.77 (figure D-34) H. Calculate Downs(ope Serm Width:Multiplier (4.G)X Downs(ope Height (4.F)=Downslope Berm Width 4.77 x 4.2 ft = 20.0 ft 1, CaLculate Minimum Berm to Cover Absorption Areo:Downstope Absorption Width (3.6 or 3.C)+4 ft.=ft 10.0 ft + � 4 � ft = 14.0 ft J. Design Downs(ope Berm =greater of 4H and 4t: 20.0 ft K. Select Ends(ope Berm Mu(tiplier: 3.00 (usually 3.0 or 4.0) L. Calcutate Ends(ope Berm (4.K)X Downslope Mound Height (4.F)=Endslope Berm Width 3.00 ft x 4.2 ft = 13.0 ft M.talculate Mound Width: Ups(ope Berm Width(4.D)+Bed Width (2.6)+Downslope Berm Width (4.J)=ft 10.0 ft + 10.0 ft + 20.0 ft = 40.0 ft N. Calcutate Mound Length:Endslope Berm Width (4.L)+Bed Length (2.C)+Ends(ope Berm Width (4.L)=ft 13.0 ft + 63.0 ft + 13.0 fc = 89.0 ft Comments: