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NLS§ 1.1, 1.2. As noted on the Denele Laboratory Soil Analysis Reports found in Appendix C, chemical analyses of the soil samples from the perc test soil borings quantify the constituents that will influence nitrate loading from this project. The important parameters for nitrate loading assessment are the organic matter, pH,cation exchange capacity (CEC), and nitrate-nitrogen content. The nitrate-nitrogen and organic matter concentrations are very low at the 30-36 inch_ depth. This suggests a low potential for future nitrate-nitrogen loading from indigenous nitrogen content within the soil. 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 slightly 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 Capacity of the soil sample is relatively low at the measured depth. This suggests there is a lower potential for the retention of ammonium molecules for microbial uptake. NLS§5.3 Table 1 below summarizes the subsurface soil characteristics encountered from the sample depth between 30-36 inches below grade: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTH SOIL NITROGEN CATION EXCHANGE pH AND Ec SOIL CONTENT CAPACITY CLASSIFICATION 30-36 In. DEPTH 3.0 ppm NO;-N 8.4 meq/100g 7.3 0.70 Fine Sandy Loam C. PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability of the on-site soils, two percolation test borings were completed adjacent to the SWC of the existing filter bed 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 48 inches was conducted to measure any permeability changes at the four ft depth in comparison to the three ft depth. As noted in Table 2 below, the perc test results of the two test depths are virtually equal. SSS§6.3. On April 14, 2014,the perc test borings were drilled in the referenced location. 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 borings. The test borings were subsequently pre-saturated with 12 inches of water at 0900 hrs, 24 hrs before the start of testing. 3