SR0056541 SSNL - Laserfiche WebLink

Home Browse Search

h Cincludipng ATEAL LENGTH AND DIAMETER ping to consist of PVC Schedule 40. As determined above,lateral length shall be 31.5 ft each lateral, the f inch clean-out sweep assembly.The diameter shall be 1 inch I.D. PERFORATION SIZE,SPACING AND NUMBER PER LATERAL Perforations shall be 5132 in. dia. For effluent distribution applications to be -4 ftZ/orifice, the spacing of perforations= 3 feet(area per orifice x no. of laterals on each side of center feed - (absorption area width) =4 ft' x 3 _5 ft= 3 ft. The number of perforations per lateral shall be: N=(p_x)+0.5 = (31.5 ft-3 ft) + 0.5 = 21 perforations per lateral x 6 laterals= 126 total perforations LATERAL DISCHARGE RATE(LDR) Recommended distal pressure is 5 ft, translates to 0.68 gpm per orifice. LDR=0.68 gpm/perforation x 11 perforations/lateral =7.5 gpm/lateral MANIFOLD AND FORCE MAIN DIAMETER The force main and manifold shall be 2.0 in. I.D., composed of PVC Schedule 40. NETWORK DISCHARGE RATE (NDR) NDR=6 laterals x 7.5 gpm/lateral =45 gpm. APPROXIMATE TOTAL DYNAMIC HEAD(TDH) The TDH cannot be accurately determined at this time since some design factors are unknown. Consequently, an estimate of the TDH is provided assuming a total distance of 35 feet from the chamber to the end distribution network for the primary mound system. The TDH the pump must work against: System network head= 1.3 (conv. factor) x distal pressure 5 ft=6.5 ft Elevation distance between the pump and the highest elevation of the distribution network =9.0 ft Friction loss in force main =7 ft(185 ft of force main+ manifold) +add-on friction loss of 8 ft= TDH: 6.5 + 9 + 7 + 8 = 31 ft k PUMP REQUIREMENTS A=duplex pump-system;each-pump puiriping 45=gprn again kt>31"feet of head. The selection based on the System Performance Curve found on the Plans. APPROXIMATE DOSE VOLUME A=dose volume of: 20°Io of.design flow'(gal/d'ADF)-shall be used=.75 gallons. This conforms with the California State Water Resources Control Board- Guidelines for the Deskon, Installation and _Operations of Mound Sewage Disposal Systems document of"recommended dosing volumes"found in Section 34.0, Page 17, Table C. Use 5 times the lateral void volume: Lateral dia. = 1.0 in. Lateral length = 31.5 ft Number of laterals= 6 Lateral void volume=0.041 gal/ft 'CNet Dose-Voluine-=5'x 31:5 x 6 x 0:041'=;77 gals/dose. Floats shall be set to dose an approximate volume of 75 gals/dose By ha"ving orifices in.thi f2 "o'clock position with shields,the pumps will not have to charge the piping .network at the time of every dose. 17 Chesney Consulting