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A denitrification factor of 60% (a 33%reduction from the observed value) will be used in the nitrate loading calculations in Section III B. Because septic effluent is composed predominately of ammonium(NH4), the pH, along with the CEC, have significant influence on ammonium molecules. The pH of the soil is alkaline which retards ammonium formation and stability. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at 25.9; indicative of high clay content soils. Consequently,there is a high potential for the retention of ammonium molecules for microbial uptake, and suppression of nitrification and promotion of denitrification that may occur. NLS§3.3, SSS§5.3. Table 1 below summarizes the surface and subsurface soil characteristics tested from the soil sample: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE LOCATION SAND,SILT AND SOIL SOIL NITROGEN pH AND (SAMPLE NUMBER) CLAY CLASSIFICATION CONTENT CATION EXCfL4.NGE PERCENTAGES CAPACITY FILTER BED DISPOSAL AREA 35%,30%,35% Clay Loam 2 ppm NO,-N 8.9 25.9 meq/100g (30-36) 36'E-W,33'N-S=1188 sf C. PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability of the proposed filter bed disposal area, a percolation test was completed in the location depicted on the Percolation Test Rate Form found in Appendix C. SSS§ 6.3. On January 11, 2021, a 36" deep percolation test boring was hand-drilled in the referenced location. The sidewall was scored with a pry-bar to open potentially smeared surfaces. Two inches of pea gravel was placed at the bottom and three-inch perforated PVC pipe was inserted to prevent cave-ins. The test boring was pre-saturated with 12 inches of water at 0800 hrs, 24 hrs before the start of testing. SSS§ 6.4,6.5. On January 12, 2021,percolation testing commenced. No standing water was observed after the 24-hr soak period. Consequently, EHD Perc Test Procedure#2 was conducted in which testing was done over a four-hour period to induce maximum soil saturation. The test results indicated a failing perc rate of 62.5 min/in, which occurred after the last half hour test reading from 11:30 to 12:00. A summary of the perc test results for the proposed disposal area with corresponding application rates in gallons of effluent accepted per square foot of soil,per day, are found in Table 2: 3 Chesney Consulting