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As illustrated on the attached landscaping plan with the septic system overlay, the area reserved for the filter bed will actually accommodate a 40 feet x 45 feet= 1,800 square feet filter bed area. Standard Capacity Infiltrator® Chambers are specified with the following dimensions:34"x750tx12" Storage Volume= 78 gallons/chamber x 66 Chambers = 5,148 gallons temporary storage capacity CONFIGURATION OF PRESSURE DISTRIBUTION NETWORK The distribution of piping must discharge the effluent uniformly over the soil/effluent interface, with closely spaced orifices so that effluent application area is -6 f12/orifice. Force main piping will be a center-feed manifold to the laterals. There will be a total of 22 Iaterals - I 1 on each side of the manifold, six inches apart and three chambers per lateral. Orifices shall be drilled with a sharp drill and installed facing per manufacturer's recommendations. Clean-outs may be provided at the distal ends of the laterals per EHD recommendations. LATERAL LENGTH AND DIAMETER Piping to consist of PVC Schedule 40. Each lateral length to be -20 ft with a diameter of 2.0 in. I.D. PERFORATION SIZE, SPACING AND NUMBER PER LATERAL Perforations shall be 3/16 in. di a. For effluent distribution applications to be -6 ft'/orifice, the spacing of perforations= (area per orifice x no. of laterals on each side of center feed (absorption area width) = 6 ftZ x 2 - 3 ft=4 ft. The number of perforations per lateral shall be; N=(p—x) + 0.5 = (20 ft . 4 ft) + 0.5 = 5 perforations per lateral x 22 laterals = 132 perforations LATERAL DISCHARGE RATE (LDR) Recommended distal pressure is 3.5 ft for 3/16 in. orifices, translates to 0.78 gpm per orifice. LDR = 0.78 gpm/perforation x 5 perforations/lateral = 4 gpm/lateral MANIFOLD AND FORCE MAIN DIAMETER The force main and manifold may be 2.0 in. I.D., composed of PVC Schedule 40. NETWORK DISCHARGE RATE (NDR) NDR=22 laterals x 4 gpm/lateral = 88 gpm. FILTER BED DOSE VOLUME EXAMPLE A dose volume of-20% of design flow(1,500 gal/d ADF) may be used. Use 3 times the lateral void volume: Lateral dia. =2.0 in. Lateral length - 20 ft Number of laterals=22 Lateral void volume = 0.163 gal/ft Net Dose Volume = 3 x 20 x 22 x 0.163 =215 gals/dose Flow through force main and manifold = 77 ft at 0.163 gal/ft (2 inch I.D.) = 13 gal/dose Floats shall be set to dose an approximate volume total of 215 gals + 13 gals z 228gals/dose r 12 Chesney Consultin