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40 <br /> DISCUSSION <br /> In general, the open fields are well suited to Conventional Type septic systems with both soil <br /> depth and gentle, consistent sloping topography and as such should be targeted for the septic <br /> drainfield for the school. When determining the area needed for the drainfield, the following <br /> equation is used to first determine the amount of drainline: <br /> Drainline=# students x student GPD /LTAR/3' trench width x 0.75 accepted system <br /> 15,6001f= 1,200 x 13 /0.25 x 3 x .75 <br /> This drainline calculation is based upon the following assumptions: <br /> • 13 GPD/student is based upon the interpretation of state rule .1949(b) of a day school <br /> with showers, no cafeteria <br /> • The 0.25 LTAR is a considered a conservative estimate. This rate may change pending <br /> additional soil testing, in particular hydraulic conductivity tests, and with input from state <br /> and/or county regulators <br /> Once the amount of drainline is determined, the area needed for the drainfield is calculated as <br /> follows: <br /> Area= drainline/ 100 ft. long drainlines x 9-foot center spacing x buffer x repair system <br /> 336,960 ft2 = 15,600 / 100 x 9 x 1.2 x repair system <br /> The area calculation is based on the following assumptions: <br /> • 100 ft drainlines, this is general starting point, can be increased or decreased <br /> • 20%buffer is factored in to allot for diverging drainline and other site factors <br /> • Repair system is using the same drainfield type as the initial system <br /> As such, 336,960 ft2 or approximately 7.75 acres will be required for the initial and repair <br /> systems. The initial and repair systems do not have to be contiguous. Further, the 168,480 ft2 <br /> required for just the initial system can be broken into separate drainfields and/or smaller systems <br /> to suit the site design. <br /> It should also be noted that the repair area(s) could be placed elsewhere on the property and <br /> could be a different system type(i.e. Drip). Additional soil testing would be required to <br /> determine the viability of this option. <br /> CONCLUSIONS <br /> The findings presented herein represent our professional opinion based on our Preliminary Soil <br /> and Site Evaluation and knowledge of the current laws and rules governing on-site wastewater <br /> systems in Orange County and North Carolina. There appears to be ample soil to accommodate <br /> the drainfield needs for a 1,200 student day school. However, once a preliminary site design is <br /> completed, additional site and soil investigations should be conducted to determine the septic <br /> system particulars. <br /> Meadowmont Farms II Tract November 21, 2021 <br /> Job 8621 <br />