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October 19� 1983 Job # 1980 <br /> Specifications� lots 31 & 32 Pa�;e 2 of 3 <br /> TREATMENT AREAs <br /> The treatment area will consist of a drainfield using SB2 tubir�g manufactured <br /> by ADS (Advanced Drainage Systems Inc). The drainfield will consist of six <br /> sections of SB2 tubing� each 20 feet long� installed in separate trenches that <br /> are separated from each other end to end by not less than 5 feet. The SB2 <br /> tubing shall be not closer than 8 feet when measured from center line to <br /> center line. The drainfield will be installed at approximately the area <br /> shown on the attached location plan� althou�;h some variation can be permitted <br /> to allow site adaption to local site features. The diameter of the tubing <br /> shall be a nominal 10 inches. <br /> The tubing shall be installed in trenches dug in the natural soil to bottom <br /> elevations of from ]b to 21� inches below existing grade. The trench width <br /> shall be 2I� inches, and the sides of the trenches shall be scarified and loose <br /> material removed prior to installing the tubing. The bottom of each 20 foot <br /> trench shaly be level, and the SB2 tubing shall be i.nstalled level in the <br /> trench. The individual sections of SB2 tubing shall be conne�ted in series <br /> so that distribution to subsequent sections occurs only after each section <br /> is filled to capaeity. The distribution sha 11 he accomplished by capping <br /> the end of each section and drawing off the top half with a solid 1t inch <br /> PVC pipe. This !t" pipe shall distribute to the next section of SB2 tubing, <br /> the invert of which will be level with or lower than the invert of the <br /> 20 foot section immediately preceeding it in lineo Excavation between <br /> individual 20 foot sections of SB2 �ubing sha11 be the minimum necessary <br /> to install the distribution pipe. It is intended that there be an earth <br /> dam of natural, undisturbed soil separating each individual 20 foo-� section <br /> of SB2 tubing. See the attached installation detail sketch. <br /> Each of the separate 20 foot sections of SB2 tubing shall have an inspection <br /> pipe installed, generally at the downstream end as indicated in the installation <br /> detail sketch. The inspec�ion pipe shall be a solid I� inch PVC pipe, cap�d <br /> at grade. A screw type inspection cap with appropriate fitting to the pipe <br /> shall be used so that a tight closure can be readily obtained after each <br /> inspection. The inspection opening sha1.1 penetrate the top of the SB2 tubing <br /> and the !� inch inspection pipe sha11 be secured above this opening to permit <br /> proper inspect?on into the bottom of the SB2 tubing. The opening shall be <br /> protected from infiltration of soil fill, The natural� excavated soil shall <br /> be used �o backfill the trenches at completion of the installation. The soil <br /> shall be loosely placed without compacting� and the finished installation shall <br /> be mounded over the tre.nch to accomodate future settling. -The location of the <br /> inspection pipe shall be marked by driving a 3/1.G inch st,eel pipe 6 inches belo�•r <br /> grade at the bottom and 1 i.nch above grade at the top. The st,eel pipe shall <br /> be driven immediately adjacent to the 1� inch i.nspection pipe. Steel s�all <br /> be used to facilitate future location with metal detectors. <br /> TOM SMITH ASSOCIATES inc <br />