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The reason for this extremely high soil nitrogen content, is due to the fact that the prior land use was as an agricultural by-product recycler. Mounds of biomass were processed and stored in this area, thus leaching nitrogen into the soil and groundwater. Because 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 has a positive effect in promoting ammonia and not the nitrate substrate ammonium within the soil environment. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. At 27.3 meq/100g,the CEC illustrates a very high potential for the clay soil to retain ammonium molecules that remain as ammonium. Nitrification is also hindered due to the alkaline pH and from the anaerobic micro-sites within the clay soil. NLS§3.3, SSS§ 5.3,5.4. Table 1 below summarizes the encountered soil physical and chemical characteristics: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTH AND SOIL SOIL NnRATE-NITROGEN pH AND (SAMPLE NUNMER ON CLASSIFICATION CONTENT CATION EXCHANGE CAPACITY -TEST RESULT FORDO) In;meq/100g BDG24 Silty Clay Loam 189 ppm NO,-N/450 Units 7.3 27.3 me /100g C. PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability in the 36" boring,which corresponds with the approximate soil-effluent interface elevation,the aforementioned percolation test borings were completed in the locations depicted on the Site Plan found in Appendix C. SSS§ 6.3. After drilling,the sidewalls of the borings were'scored with a pry-bar to open potentially smeared soil surfaces that may have occurred due to the clay soil,-and the cuttings removed. Two inches of gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in each test boring. After these procedures, the borings were pre-saturated with 12 inches of water approximately 24 hrs prior to the start of testing. SSS§6.4, 6.5. On February 25, 2019,percolation testing commenced at 0800 hrs. No standing water was observed after the 24-hr soak period. Consequently, EHD Perc Test Procedure#2 was conducted. Testing was done over a four-hour period to induce maximum soil saturation,which was easily achieved since this rainy season was one of the heaviest on record. Page -3- Chesney Consulting