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1 <br /> PRESSURE DISTRIBUTION SYSTEM Geotextile fabric <br /> 1. Select number of erforted laterals n 12 <br /> p / Quarter inch perforations spaced 0 3' <br /> tom'-i?s., t. 9 of:rack <br /> 2. Select pjerforation spacing= 3. 0 ft t;=z ji.-r,',:.e <br /> an--,. 2,-,, <br /> 31-zt1"=tt Perf Sizin3 <br /> az-� >>+t=t �fotYkti.= S� PerfSpacing 115'-5' <br /> 6"-1/4" <br /> 3. Since perforations shoul not be placed closer than 1 foot to <br /> the edge of the rock layer (see diagram),subtract 2 feet from <br /> the rock layer length. E-4: Maximum allowable number of 1/4-inch perforations <br /> per laterd to guarantee<10%discharge variation <br /> Rock layer length! -2 ft = ft perforation <br /> 4. Determine the number o spaces between perforations. spacing <br /> Divide the length (3)by erforation spacing(2)and round (feet) 1 inch 1.25 inch 1.5 inch 2.0 inch <br /> 2.5 8 14 <br /> clown to nearest whole n ber. <br /> 18 28 <br /> Perforation spacing ft+ ft= spaces 3.0 8 13 17 26 <br /> 3.3 7 12 16 25 <br /> 5. Number of perforations is equal to one plus the number of <br /> 4.0 7 11 15 23 <br /> perforation spaces(4). Check figure E-4 to assure the number of <br /> perforations per lateral guarantees <10%discharge variation. 5.0 6 10 14 22 <br /> spaces + 1 = perforations/lateral E-6: Perforation Discharge in gpm <br /> 6. A. Total number of perfo ations = perforations per lateral (5) perforation diameter <br /> times number of laterals(1) head inches) <br /> (feet) 3/16 7/32 1/4 <br /> perfs/lat x__1 ___lat= 5 8 perforations <br /> 1.00 0.42 0.56 0.74 <br /> B. Calculate the square footage per perforation. <br /> 2.0b 0.59 0.80 1.04 <br /> Should be 6-10 sqft/per . Does not apply to at-grades. <br /> Rock bed area = rock w dth (ft)x rock length(ft) 5.0 0.94 1.26 1.65 <br /> ft x ft 90 0 sqft ° Use 1.0 foot for single-family homes. <br /> Square foot per perfora 'on = Rock bed area +number of perfs (6) b Use 2.0 feet for anything else. <br /> C'Do sqft+ 5' / perfs= /(0 sqft/perf <br /> MANIFOLD LOCATED AT END OF PRESSURE DISTRIBUTION SYSTEM <br /> 7. Determine required flow rate by multiplying the total number of <br /> perforations (6A) by flow per perforation(see figure E-6) <br /> perfs x : )y gpm/perfs= `-13 gpm `'� � <br /> Mgr <br /> 8. If laterals are connected to header pipe as shown on upper <br /> example,to select minim required lateral diameter;enter " T"`"00, ' °M " <br /> figure E-4 with perforatio spacing (2)and number of perforations `"`"�d <br /> per lateral(5) Select . ' um diameter for <br /> perforated lateral= I �1 Z- <br /> LAYOUTOF mCPCDIMINUTION <br /> Pln RI MOUND roR <br /> inches. PRESSURE DIfTRIfY71DN W MOUND <br /> KRIOIYTIC PLASTIC Mf <br /> 9. If perforated lateral system is attached to manifold pipe near <br /> �,�,,„�, <br /> the center,lower diagram,perforated lateral length (3) and °'° Anker , 1a K""""�AW <br /> number of perforations per lateral (5)will be approximately one KR,sas , TIOr M - <br /> half of that in step 8. Using these values,select minimum .. wDw-4 <br /> diameter for perforated lateral= inches. 4D?,. a <br /> „IRLL <br /> „ � <br /> d <br /> I hereby certify that I have completed this work in accordance with applicable ordinances, rules and laws. <br /> g- 4X.__L_ ___I (signature) 3`,N (license#) `-)-a`-1-0 Z (date) <br /> - <br />