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�Becauseptic effluent is composed predominately of ammonium (NH,), the pH, along with the CEC, are significant influences on ammonium molecules. The pH of the soil is acidic at the surface but alkaline at the deeper depths which may have an effect on ammonium formation and stability. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange Capacities of the soil samples are comparatively low, except at the surface. This ti> suggests there is a low-to-medium potential for the retention of ammonium molecules for microbial uptake. NLS§ 3.3, SSS§ 5.3, 5.4. Table 1 below summarizes the surface and subsurface soil physical and chemical characteristics from the six soil samples retrieved from the exploratory boring: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTH AND SAND,SILT AND SOIL SOH,NITRATE- pH AND (SAMPLE NUMBER ON CLAY CLASSIFICATION NITROGEN CATION EXCHANGE TEST RESULT FORM) PERCENTAGES CONTENT CAPACITY 0 FT DEPTH 37%, 30%, 33% Clay Loam 13 ppm NOS N 6.7 17.9 meq/1008 5 FT DEPTH 41%,36%,23% Loam 8 ppm NO;N 7.8 12.8 meq/1009 10 FT DEPTH 87%, 6%,7% Loamy Sand 7 ppm NO,N 8.3 4.5 meq/100g 15 FT DEPTH 31%,36%,33% Clay Loam 11 ppm NO;N 7.7 9.5 meq/100g 20 FT DEPTH 65%, 16%, 19% Sandy Loam 7 ppm NON 7.8 7.7 meq/1008 25 FT DEPTH 45%, 28%,27% Clay Loam 7 ppm NO,-N 7.5 9.7 meq/1009 C. PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability at prescribed depths of the on-site soils, the aforementioned four percolation test borings were completed in the locations depicted on the District Viewer Map (le S) found in Appendix C. SSS§ 6.3. After drilling the perc test borings, the sidewalls of the shallow boring was scored with a pry-bar to open potentially smeared sidewalls. The deeper borings could not be scored due to their depths. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was 3� inserted in each test boring. On October 14, 2007, each boring was pre-saturated with 12 inches of water at 0900 hrs, 24 hrs before the start of testing. SSS§ 6.4, 6.5. On October 15, 2007, percolation testing commenced. Approximately four inches of standing water was observed after the 24-hr soak period in the 42-inch deep hole, consequently, u EHD Perc Test Procedure#I was conducted for this test boring. 4 Chesney Consulting