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The nitrate-nitrogen concentrations are very low at both test depths of two feet and four feet in comparison to normal agronomic concentrations. This suggests a low potential for future nitrate-nitrogen loading from indigenous nitrogen content within the soil. Although the four foot depth is slightly more than three times the nitrate-nitrogen concentration of the two foot depth concentration,this may be attributable to denitrification. Since septic effluent is composed predominately of ammonium(NH4),the pH, along with the CEC, are significant influences on ammonium molecules. The pH of the soil is alkaline which may inhibit ammonium formation and stability, and may create a propensity for ammonia(NH3)formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange Capacities of the soil samples are high at the four foot depth. This suggests a greater potential for the retention of ammonium molecules for microbial uptake,and suppression of nitrification. §5.3 Table 2 below summarizes the subsurface soil characteristics encountered from the two sample depths below grade: TABLE 2 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTHSOIL NITROGEN CATION EXCHANGE PH AND EC SOIL CONTENT CAPACITY CLASSIFICATION 2 FT DEPTH 4.0 ppm NON 9.5 meq/100g 7.7 0.71 - Sandy Loam 4 FT DEPTH 13.0 vvm NO-N 19.5 m /100 7.7 2.88 Sandy Loam C. PERCOLATION TEST RESULTS SSS§6.2. To assess the permeability of the on-site soils,two percolation test borings were completed in the proposed leachfield location as depicted in the Site Plan found in Appendix A. The"EHD Official'perc test depth at 36 inches below existing grade gives a comparatively detailed observation of subsurface permeability from approximately 30 to 36 inches in depth. The second test depth at 24 inches was conducted to measure permeability at the proposed soil-effluent interface. As noted in Table 3 below,both test borings possess rapid permeability. SSS§6.3. On May 8,2012,the perc test borings were drilled in the referenced locations. The sidewalls of the borings were scored with a pry-bar to open potentially smeared sidewalls. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in the two borings. The test borings were pre-saturated with 12 inches of water at 0900 bra,24 hrs before the start of testing. SSS§6.4,6.5. On May 9,2012,percolation testing commenced. No standing water was observed after the 24-hr so od in either test boring. Consequently,EHD Perc Test Procedure#2 was conducted in which test' was done over afour-hour period to induce maximum soil saturation. The test results indicate a pert ra at 5.6 utes per inch(min/in) for both test borings,theoretically indicating similar soil structures at the Ito depths. summary of the perc test results with corresponding application rates in gallons of effluent act per square foot of soil,per day are found in Table 3: 3