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5.0 Mound Installation Guidelines <br /> 1. Ensure all components leading to the GSF system are installed properly. Septic tank effluent filters are <br /> required with the GSF system. <br /> 2. Determine the number of GSF Modules required using the sizing formula. <br /> 3. Prepare the site. Do not install a system on saturated ground or wet soils that are smeared during <br /> preparation. Keep machinery off infiltrative areas. <br /> 4. Plan all drainage requirements above (up-slope) of the system. Set soil grades to ensure that storm <br /> water drainage and ground water is diverted away from the absorption area once the system is <br /> complete. <br /> 5. Remove the organic soil layer. Prepare the receiving layer to maximize the interface between the native <br /> soil and Specified Sand. Minimize walking in the absorption area prior to placement of the Specified <br /> Sand to avoid soil compaction. <br /> 6. Place fill material meeting local requirements (or Specified Sand requirements) onto the soil interface <br /> as you move down the excavated area. Place specified sand in a 6" lift, stabilize by foot, a hand held <br /> tamping tool or a portable vibrating compactor. The stabilized height below the GSF module must shall <br /> meet the mound design requirements. <br /> 7. Place GSF modules with PAINTED STRIPE FACING UP, end to end on top of the specified sand along <br /> their 4-foot length. <br /> 8. A standard perforated 4-inch distribution pipe is centered along the modules 4-inch length. Orifices are <br /> set at the 4 & 8 o'clock position. <br /> 9. All distribution pipes are secured with manufacturers supplied wire clamps, one per module. <br /> 10. (Pressure Distribution Systems) Insert a PVC Sch. 40 pressure pipe (size per design and code) into <br /> the standard perforated distribution pipe. The pressure pipe orifices are set at the 12 o'clock position <br /> as shown in Figure 13. Each pressure lateral will have a drain hole at the 6 o'clock position. Each <br /> pressure lateral shall include sweeping cleanouts at the terminal ends and be accessible from grade. <br /> 11. Cover fabric substitution is not allowed. The installer should lay the Eljen provided geotextile cover <br /> fabric lengthwise down the row, with the fabric fitted to the perforated pipe on top of the GSF <br /> modules. Fabric should be neither too loose, nor too tight. The correct tension of the cover fabric is <br /> set by: <br /> a. Spreading the cover fabric over the top of the module and down both sides of the module <br /> with the cover fabric tented over the top of the perforated distribution pipe. <br /> b. Place shovelfuls of Specified Sand directly over the pipe area allowing the cover fabric to <br /> form a mostly vertical orientation along the sides of the pipe. Repeat this step moving down <br /> the pipe. <br /> 12. Ensure there is 6 inches of specified sand surrounding the GSF modules in the mound. Slope the sand <br /> away from the mound as described on the plan. <br /> 13. Complete backfill with a minimum of 6 inches of cover material measured from the top of the distribution <br /> pipe. Use well graded native soil fill that is clean, porous and devoid of large rocks. Do not use wheeled <br /> equipment over the system. A light track machine may be used with caution, avoiding crushing or <br /> shifting of pipe assembly. Divert surface runoff from the system. Finish grade to prevent surface <br /> ponding. Topsoil and seed system area to protect from erosion. <br /> 14. Divert surface runoff from the system. Finish grade to prevent surface ponding. Topsoil and seed <br /> system area to protect from erosion. <br /> 2022 California Design&Installation Manual Page 19 www.eljen.com <br />