Laserfiche WebLink
Designed By: September 17, 1998 <br /> Septic•EvaluaVons lac. Ann Carpentier <br /> Chanhassen, MN MOUND DESIGN WORKSHEET <br /> (612)470-4024 (For Flows up to 1200 gpd) 301 Willow spin <br /> Orono, Hennepin Co. <br /> Lic. <br /> A. FLOW 8aimeoee sewage Raft at CWW=W my <br /> Estimated 450 gpdIVwf ya <br /> TW , m <br /> or measured x 1.5= gpd. ° <br /> 2 300 2u 180 <br /> B. SEPTIC TANK LIQUID VOLUMES i 6o rn218 <br /> VWM <br /> 1000 gallons 6 9W 525 �Typel <br /> 7 1060 600 370 Ha <br /> $ 1200 675 409 p1 <br /> C. SOILS(refer to site evaluation) <br /> 1. Depth to restricting layer= 24 inches 2.o feet <br /> 2. Depth of percolation tests= 12 inches cw <br /> 3. Texture Cla Y Loam Percolation rate 40 mpi 23� w ism lam <br /> 4. Land slope 6 % 7'.wg 1= 3M 44M <br /> D. ROCK LAYER DMENSIONS <br /> 1. Multiply flow rate by 0.83 to obtain required area of rock layer: A x 0.83= <br /> 450 gpd x 0.83 sq. ft./gpd = 374 sq.ft. <br /> 2. Select width of rock layer(max 10'if<120 mpi max 5')= 1 ft. <br /> 3. Length of rock layer=area-#-width <br /> = <br /> 374 sq. ft.+ 10 ft. = 37 ft. <br /> Width 1 o ft <br /> <120mpi<10' Length. 37 ft <br /> E. ROCK VOLUME >120mpi<5' <br /> 1. Multiply rock area by rock depth to get cubic feet of rock, 374 sq.ft. x i <br /> ft. = 374 Cu.ft. <br /> 2. Divide cu. ft.by 27 cu.ft./cu.yd. to get cubic yards; <br /> 374 cu. ft. +27= 14 cu.yd. <br /> 3. Multiply cubic yards by 1.4 to get weight of rock in tons; 14 cu.yd.x 1.4 <br /> ton/cu.yd.= 19 tons. <br /> F. ABSORPTION WIDTH <br /> 1. Percolation rate in top 12 inches of soil is 40 mpi F� earoa.wfti. CWkm RodmatermM" <br /> Texture---2!2y Loam '�"" '°°" s°"'T�`""a pa6ij �� <br /> FiN0.Ia901 ntSad 1..D 1= <br /> 2. Select allowable soil loading rate from table; a1 as FvwSwd 0.60 am <br /> 6 w 15Sandy l ono Q79 1.54 <br /> 0.45 d/ft2 1630 30 ,.e,� 0.60 zoo <br /> 31 ooO Sibt.cw 050 2.40 <br /> 46»60 Clay Lm a 0.1S 2V <br /> 3. Calculate adsorption width ratio by dividing rock layer <br /> 60 to <br /> i2D 4 020 sb.W <br /> loading rate of 1.20 gpd/ft2 by allowable soil loading rate; <br /> 1.20 gpd/ft2+ 0.45 gpd/ft2= 2.67 <br /> 4. Multiply adsorption width ratio by rock layer width to get <br /> required adsorption width; <br /> 2.67 x 10 f t= 27 ft ©1997 Metonie L. Elvebak <br />