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FNLS! SS§ The designed Chambered filter bed that will be placed high in elevationver) take advantage of the indigenous clay soils that possess favorable qualities tocation. For nitrification that does occur, the anaerobic microsites at deeper elevationslay soils may promote denitrification. This was apparently evidenced by the soil test �!.2r the proposed and existing disposal fields. The denitrification potential in combination <br /> with landscape plants in the filter bed area should also reduce nitrate impact by evapotranspiring a <br /> percentage of the effluent through the louvers during favorable weather times of the year(i.e., April <br /> through September). <br /> SSS 6.8 he actual infiltrative surface(IS)under each Infiltrator Chamber is 6.25 ft x 2.83 ft= <br /> 17.69 17.69 ft' 160 Standard Infiltrator Chambers SC =2,830 ft'. If the <br /> is taken to be 2,108 gals/day, the Application Rate=2,108 gpd-2,830 ft' 0.=galsif�­/daaTaking an average of the application rates derived from each percolation test del <br /> profile to five feet in depth to have an average acceptance rate o . gals/ft / a . <br /> NLS )The nitrate loading potential calculated on P 1 indicates the percolating effluent <br /> may e a resultant nitrate-nitrogen concentration of 10 m,which is at the drinking water <br /> Maximum Contaminant Level(MCL). These calcula i ns rely on numerous factors which are <br /> extremely variable and unknown at this time. These factors and the effluent quality itself can only <br /> by quantified after complete build-out of the project and an actual effluent sample obtained for <br /> analysis. <br /> With regard to the calculated nitrate-nitrogen loading to the underlying groundwater table, it is <br /> important to recognize that when adding one concentration of a solute(e.g., NO3-N concentration <br /> determined in the effluent recharge) to another concentration of a solute (e.g.,NO3 N concentration <br /> determined in groundwater table), where both solutes are in ppm, the result is not cumulative or the <br /> sum of the two solutes. Parts per million is amass ratio (mg per106 mg). For example, the Nr(the <br /> resultant average concentration of nitrate-nitrogen in effluent recharge in ppm of NO3-N), was <br /> determined to be 10.0 ppm by the Hantzsche-Finnemore Equation. This equals 10.0 milligrams of <br /> nitrate in 106 milligrams of water(one liter). If this 10.0 ppm concentration is added to the same <br /> volume of water(1 x 106 milligrams) of the concentration determined in the underlying water table, <br /> which was 9.4 ppm N0;N(42 ppm NO3), then the resultant concentration is now: 10.0 milligrams <br /> per liter+9.4 milligrams per liter= 19.4 milligrams in 2 x 106 milligrams (2 liters, or parts per 2 <br /> million) of water. Therefore, to convert back to ppm, the numerator and denominator must be <br /> divided by 2 with the result of 9.7 milligrams NO3 N per 1 x 106 milligrams, or 43.2 ppm nitrate <br /> NO3. Therefore, the mixing layer located at the top of the first aquifer consisting of recharge <br /> effluent and native phreatic groundwater theoretically will not exceed the drinking water standard of <br /> 10 ppm nitrate-nitrogen NO3-N, or 45 ppm nitrate NO3. <br /> 18 <br /> Chesney Consulting <br />