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3. ABSORPTION AREA SIZING Note:Mound setbacks are measured from the Absorption Area. A. Calculate Absorption Width:Bed Width (2.6)X Mound Absorption Ratio (1.F)=Absorption Width 10.0 ft x 2.6 = 26.0 ft B. For slopes>1%,the Absorption Width is meawred downhill from the upslope edge of the Bed. Calculate Downs(ope 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 Condition (1.C)=C(ean Sand Lift (1 ft minimum) 3.0 ft - 1.7 ft = 1.3 ft Design Sand Lift (optional): �1.3 B, Calculate Upslope Height:C(ean Sand Lift (4.A)+media depth (1 ft.)+cover (1 ft.) =Upslope Height 1.3 ft + 1,0 ft + 1.0 ft= 3.3 ft -,--;--T--7---,--�---r-•------ - Land Siope 'o T i� 1 � a � 5�6 + 7 � 8�i 10� Ii ; 11 i 13 j 14 ; i5; t6 � II � 18 ; I9 ', 2u ti Ttt� 23� ta 2S : - i �. � ��i{['' 't�E _SI�'.S�' Ja ..l.�;:_f .I+.'�.[� i'.l�'� ,'?�� ; i�TT'L4i 5'I y. I.S;i ,i ' 1.�4 !.:'.;. -1-�';-- •� . --+--t--?"- -T-- (ll7 S'�) I i I:� ) I� 7 ��'. (, .c � .t �l I>> � � � ai�'�.� ,8. . 03.57�3.dS >>f�>.�, 31't�3o�;..9�b�,� .�,�� , 2i �Sj:a ,,2 i5�<_9�22;' I �2J;i S��I.��i lYBil,v;'�� .and Slope��', � �� ; I ; 2 3 i 4 5 �-.6 1 ,� 9 �9 i 0� i� ; ti ; la � I5 ; 10 �, I7 ; 18 '�� 19 �� 2�1 �12 ! 23 I t4 I 2S �� � + I r I � J. . . � � , a .,-r .. �. .: '. .. ,U�`; 7 . ��.��';I �'.56i�2�:�.7),,.11I,:Y�'.J�i .o� . . . �`�� E..�ar�.f�� '.`�� d i �. 19a[ �2.'--'-�'---� F,� �r a,!��. '.i7;a.;S�a 6�,C�J�S.2E S�h,�°dl�6 5�5.6',7.N��t� „_yloi�'95.j1� JII(i.5a�i116?il2_a21 ' Ir� �Y9i a3'I�S61�� ;�� Select Upslope Berm Mu(tip(ier �' (based on land slope): 3.03 (figure D-34) D. Calculate Upslope Berm Width:Multip(ier (4.C)X Ups(ope Mound Height (4.6)=Ups(ope Berm Width 3.03 ft x 3.3 ft = 10.1 ft E. Calculate Drop in Elevation Under Bed:Bed Width (2.6) X Land 5(ope (1.D)=100=Drop (ft) 10.0 ft X 8.0 % r 100= 0.80 ft F. Calculate Downslope Mound Height:Upslope Neight (4.B)+Drop in Elevation (4.E)=Downs(ope Height 3.3 ft + 0.80 ft = 4.1 ft G Select Downslope Berm Multip(ier (based on land slope): 5.88 (figure D-34) H. Calculate Downs(ope Berm Width:Multip(ier (4.G)X Downslope Height (4.F)=Downs(ope Berm Width 5.88 x 4.1 ft = 24.3 ft I. Calculate M�nimum 8erm to Cover Absorption Area:Downs(ope Absorption Width (3.B or 3.C)+4 ft. =ft 16.0 ft + �4 ft = 20.0 ft J. Desfgn Downslope Berm =greater of 4H and 41: 24.3 ft K. Select Endslope Berm Multiplier: 4.00 (uwally 3.0 or 4.0) L. Catculate Endslope Berm (4.K)X Downs(ope Mound Height (4.F)=Endstope Berm Width 4.00 ft X 4.1 ft = 16.5 ft M. Calculate Mound Width: Ups/ope Berm Width(4.D)+Bed Width (2.6)+Downslope Berm Width (4.J)=ft 10.1 ft + 10.0 ft + 24.3 ft = 44.4 ft N. Calculate Mound Length:Endslope Berm Width (4.L)+8ed Length (2.C)+Ends[ope Berm Width (4.L) =ft 16.5 ft + 26.0 ft + • 16.5 ft = 59.1 ft Comments: Mound A, Upper Unit.