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3. ABSORPTION AREA SIZING Note:Mound seibacks are measured from the Absorption Area. A. Calculate Absorption Width:Bed Width (2.B)X Mound Absorption Ratio (1.F)=Absorption Width 10.0 ft x 2.6 = 26.0 ft B. For slopes>t%, the Absorption Width is measured downhill from the upstope edge of the Bed. Calculate Downslope Absorption Width:Absorption Width (3.A)-Bed Width (2.6)=ft 26.0 ft - 10.0 ft = 16.0 ft 4. MOUND SIZING A. Calculate Clean Sand lift: 3 feet minus Depth to Limiting Conditfon (1.C)=C(ean Sand Lift (1 ft minimum) 3.0 ft - 2.1 ft = 1.0 ft Design Sand Lift(optional): �1.0 B. Calculate Ups(ope Height:Clean Sand Lift (4.A)+media depth (1 ft.) +cover (1 ft.)=Upslope Height 1.0 ft + 1.0 ft + 1.0 ft= 3.0 ft . >:. . . . ----r-. �--�---T---__ LandSlope��, �� 0 �� i �i i �, 3 ; ai5lb '� 7 �� 8 �9i�olti '�� iil �� ia isi �o �� i1 ; �a ' ivji�i �� ti �; it ilita t5 -r--� , + �---•- t -�---,---!-, -- �� .; '��.i^ vl'�,-:;� �51��,i�'I' �,�.1bi ��:5' i '��: 11 � -'f� d6� ��.i.tk �, �.5 , 1.59� r� '� I.� I.''r�1.� `., E r�� t �� 4d�� .1Q1,5 i..J�,1,i3.1 i30� 1�.9d�2- 6�27�i't'�t S��.S9 a8i 1 a1 �2 35. 2.29�1 2;�LIf i 2 t�i 2.Da!2 0s �.ye� ��i� . �_�-- -r-- �� LandSlope � ' 0 �� i . i ; 3iaiS � n � 7 8I9 ; ioiii � il � �3 �; ia i5 ': io ! U + i8 ` I9 ; 20 ; ti �, ii �I1i ; tal �;�� .. I - +. .� �i�� 'll 5h;,C'L�r)�.,�I, r f.= �� .� �F i �J,� ',d � ,� �.J��`Jo - �_'+� ,�-�--�r-~.:'5.�1:St6;.F�,;S,��.::5'�� I..'n> .�: �i� ��I .•d ill'f.'II.F,��11 � .,�r Yr�l'�a.d. `i. ,�.c� -.. Select Upslope Berm Multiplier �' (based on land slope): 2.55 (figure D-34) D. Calculate Ups(ope Berm Width: Multiplier (4.C)X Upslope Mound Height (4.6)=Upslope Berm Width 2.55 ft X 3.0 ft = 7.7 ft E. Calculate Drop in Elevation Under Bed:Bed Width (2.6) X Land Slope (1.D)=100=Drop (ft) 10.0 ft X 14.0 % � 100= 1.40 ft F. Calculate Downslope Mound Height:Upslope Height (4.6)+Drop in Elevation (4.E)=Downs(ope Height 3.0 ft + 1.40 ft = 4.4 ft Select Downslope Berm Multiplier �� (based on land slope): 8.92 (figure D-34) H. Calculate Downs(ope Berm Width:Mu(tiplier (4.G)X Downslope Height (4.F)=Downslope Berm Width 8.92 x 4.4 ft = 39.2 ft I. Calculate Minimum Berm to Cover Absorption Area:Downslope Absorption Width (3.6 or 3.C)+4 ft. =ft 16.0 ft + �4� ft = 20.0 ft J. Design Downs(ope 8erm =greater of 4H and 41: 39.2 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)=Ends(ope Berm Width 4.00 fc x 4.4 ft = 17.6 ft M.Calculate Mound Width: Upstope Berm Width(4.D)+Bed Width (2.6)+pownslope Berm Wfdth (4.J)=ft 7.7 ft + 10.0 ft + 39.2 ft = 56.9 ft N. Calculate Mound Length: Ends(ope Berm Width (4.L)+Bed Length (2.C)+Endslope Berm Width (4.L)=ft 17.6 ft + 26.0 ft + ' 17,6 ft = 61.2 ft Comments: Mound A, Upper Unit.