1992-004708 - new septic system - Laserfiche WebLink

Home Browse Search

. ' . . .Tir� ,h��,�sa.,� , � 6�'r�,��✓�.�s �,-Zo PfOUND DESIGN PROCEDURE (Continued) (For Flows up to 1200 gpd) � G.3. Calculate basal width ratio H.2.f, riultiply dike multiplier by by dividing rock layer downslope mound height to get loading rate of 1.20 gpd/ft2 downslope dike width; by allowable soil loading ,j.5�6 X.,� 7. =10, 6 ft rate; 1.20 gpdi f t� �O._.5gpd/f t2 = Z, y0 �• Compare the values of step H. 1 , - and step H.2.f. Select the Check this value on page E-16, greater of the two values as 4. Multiply b�sal width ratio by the downslope dike width; rock layer width to get 1Q��,6.:'� feet required basal width; , h. Calculate upslope dike width .,Z� �s�'D x /O f t =2y O f t , , using upslope mound height � and upslope dike multiplier H. Downslope Dike Width fram page �'-18• .3�L1 :c �.o = ' g - f t 1. If landslope is 3% or more, i. Total mound widt�i is the sum subtract rock layer width of upslope dike width plus rock from basal width to obtain layer width plus downslope d��:e minimum do�,mslope dike toe w'idth widtn• y.�� ft - �ft =�y Oft � /n. S/ft�+ /Q ft +��.�ift = L�d.OtC 2. Calculate mound height at edge 3. If landslope is 2.9 percent or of rock layer on. docanslope side; less, basal width includes botti a. Determine depth of clean sand the upslope and downslope dike fill at upslope edge of rock widtlis. layer: /, O feet b. Tfultiply rock layer width by a. Calculate downslope dike width landslope to determine drop using steps H.2.a. throup,h in elevation; H.2.f; feet �O x �% = 100 =�. �ft b. Calculare upslope dike width c. Add drop in elevation to depth usinh upslope mound hei�ht and of clean sand at upslope ed�e dike multiplier from Page �-18; of rock layer �to get depth of a f t = f t clean sand at downslope edge � c. Add downslope dike width to of rock layer. upsZope dike width to rock Q„ 7'ft + /. Oft = �. 7ft layer width to get total mound d. Add depth of clean sand at down- width; slope edge to depth of rock it + ft + ft = ft layer to depth of soil backfill — to get mound height at downslope d• Comoare total mound wicltti to edge of rock layer;' required basal width from step � .�ft +/,- Oft +/,Oft =,3. �ft G.4 . If total mound width is � greater than required basal e. Enter table on page �-13 with width, use calculated dike landslope and downslope dike widths. If required basal ratio. Select dike multiplier widtn is greater than total of .S. S� y;/ ,f�dPC mou.^.d width, increase dowilslone dike width.