Laserfiche WebLink
C 0�CJ G.J'��,cr-c.� - Ic .• 0 fa a r'Ul--0 <br /> MOUND DESIGN WORK SHEET (For Flows up to 1200 gpd) <br /> A. Average Design FLOW <br /> S t st.d0 <br /> A-1: Estimated Sewage Flows in Gallons per Day <br /> r <br /> Estimated number of gpd (see figure A- ) bedrooms Class I Class II Class III Class IV <br /> or measured x 1.5 (safety factor) 225 180 60% <br /> .drab <br /> = gpd450 300 218 of the <br /> B. SEPTIC TANK Capacity 4 X50 375 256 values <br /> p ty 5 750 450 294 in the <br /> 6 900 525 332 Class I, <br /> 2 — (00 0 gallons (see figure C-1) 7 1050 600 370 II,or III <br /> 8 1200 675 408 columns. <br /> C. SOILS (refer to site evaluation) C-1: Septic Tank Capacities(in_gallons) <br /> Liquid capacity <br /> /� `� '�� feet Number of Minimum Liquid Liquid capacity with with disposal& <br /> 1. Depth to restricting layer = Bedrooms Capacity garbage disposal lift inside <br /> 2. Depth of_percolation tests = /, 6 feet 1125 1500 <br /> -(Q 4'/rte C. c) � of e 2 1000 2250 3000 <br /> 1500 2000 <br /> 2 <br /> 3. Texture /4(0,670 inipt 7,s or 9 2000 3000 4000 <br /> Percolation rate /1, / mpi <br /> 4. Soil loading rate 0 • 41.5- gpd/sqft (see figure D-33) <br /> 5. Percent land slope a-C % <br /> D. ROCK LAYER DIMENSIONS <br /> 1. Multiply average design flow (A)by 0.83 to obtain required rock layer ar a..,� <br /> S•r) gP d x 0.83 sqft/gpd = 'S 7 5/ sqft-,,- /c% = .50`a <br /> 2. Determine rock layer width = 0.83 sqft/gpd x linear Loading Rate (LLR) <br /> 0.83 sqft/gpd x l 2 gpd/sqft = /0 ft Mound LLR <br /> 3. Len th of rock layer = area ± width. _ <br /> .‘74/o sqft (D1) ± /0 ft (D2) =�/v ft 0_1_120 MPI <12 <br /> E. ROCK VOLUME > 120 MPI < 6 <br /> 1. Multiply rock area (D1) 0y rock depth of 1 ft to get cubic feet of rock <br /> "-/-/C> sqft x 1 ft d cuft <br /> 2. Divide cuft by 27 cuft/cuyd to get cubic yards <br /> "1/C) • cuft ± 27 cuyd/cuft = /6 cuyd <br /> 3. Multiply cubic yards by 1.4 to get weight of rock in tons <br /> /Co cuyd x 1.4 ton/cuyd = 7-3 tons /G cJ/6 <br /> D-33: Absorption Width Sizing Table <br /> F. SEWAGE ABSORPTION WIDTH Percolation Rale Loading Rate <br /> in Minutes per Sod lexiwe as nsAbsorption <br /> Inch pery per <br /> (MPI) square toot <br /> Faster than 5 Coarse Sand 1.20 1.00 <br /> Medium Sand <br /> Loamy Sana <br /> . Absorption width equals absorption ratio (See Figure D-33) Ra Sand <br /> s to 15 sandy Ldam 0 019 1.50 <br /> times rock layer width (D2) 16 to 30 Loan, .60 200 <br /> 31 to 4� Sill Loam 0.50 40 <br /> � Silt ----....--...///\JJJ <br /> 7 andy Clay OA5 .67 <br /> L2, )( �u ft = �'� ft /� Silty Clay <br /> Loam <br /> m <br /> 04-1L //�y lry..1/ ( 4 1A—) 61 to 120 Clay Loam 0.24 5.00 <br /> _�1/"("n' Silty Clay <br /> /• <br /> /�,.` i Sandy Clay <br /> ONSIT! i '- Slower elan 120' Clay <br /> SEWAGE <br /> TREATMENT r P . Orr, <br /> PROGRAM <br />