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denitrification. It may be theorized that this is what is occurring when the percolating water"pools" on top of this higher porosity soil,thus creating an anaerobic environment thus causing the illustrated decrease in nitrate-nitrogen concentration from 2 ppm to I ppm. Additionally,this stratum is most likely anaerobic when seasonally saturated, further creating a favorable denitrifying environment. 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 acidic to neutral throughout the soil profile which may have a positive 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 illustrate decreasing CEC with increasing depth. This suggests a higher potential for the retention of ammonium molecules for microbial assimilation in the soils at the 24inch depth versus the 42-inch depth. LS§3.3 SSS3y(�_._4. Table 1 below summarizes the analyzed soil physical and chemical ristics froili the retrieved two soil samples: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS =CLASSIFICATION SOIL NITRATE- pH AND ATION NITROGEN CONTENT CATION EXCHANGE CAPACITY In meq/1008 Sand 2 ppm NO,-N 6.1 5.7meq/100g 1 m NO-N 7.0 3.3 me /100 C. PERCOLATION TEST RESULTS SS .2 4o assess the permeability at the prescribed depths of the native soils, the two afexlfentioned percolation test borings were completed in the locations depicted on the attached aerial photo, which are within the 100 ft radius of the proposed filter bed location. 'SSS§ 6.3. After drilling the test borings,the sidewalls 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 each test boring. After the drilling procedures, each boring was pre-saturated with 12 inches of water --24 hrs prior to the start of testing. �/89S§6.4,6.5. On July 28, 2015,�percolation testing commenced at 0700 his. No standing water was observed after the 24-hr soak period in both test borings. Consequently, EHD Perc Test Procedure #2 was conducted. Testing was done over a four-hour period to induce maximum soil saturation. The test results indicate rapid permeability at both depths with a slightly higher permeability at the 42-inch depth versus the 24-inch depth, which corresponds with the observed soil classification. The perc rates observed are rapid enough to incorporate mitigation procedures. This will be discussed in the Conclusions Section of this Report. 3