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types. As referenced, a soil sample was retrieved from the 38-inch deep perc test boring for physical and chemical analyses. The attached texture analysis reveals the on-site soils at this depth consists of a loam, with sand, silt and clay percentages of 44%, 30%and 26%respectively. The clay content of the on-site soils can be considered significant for denitrification potential. NLS§ 1.2. As noted on the attached Soil Analysis Report,the chemical analyses conducted quantifies several constituents that influence nitrate loading for this project. The important parameters for nitrate loading assessment are the organic matter and estimated nitrogen release (ENR), clay content, pH, cation exchange capacity(CEC), and the nitrate-nitrogen content of the soil. The organic matter is low at 1.4%. The ENR is a medium 57 lbs/ac. This OM and ENR concentrations suggest there is a low-to-medium potential for future nitrate forming from organic matter. As nitrate molecules that may form from the septic effluent percolate downward,these molecules travel into and through the clay soil. This soil type is generally anaerobic under wet conditions,thus promoting denitrification and inhibiting nitrification. Since 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 may have the effect of promoting ammonia formation and not ammonium formation. Since ammonium is the precursor to nitrate formation, if NH3 is promoted, this will retard NH4 formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at 14.8 meq/100 g, which is a medium-high value. This suggests a medium-high potential for the retention of ammonium molecules that may form for microbial assimilation within the soil. The nitrate-nitrogen is a low concentration at 8 ppm illustrating that nitrogen fertilizers have been carefully applied to the walnut crop, and also indicating a low potential for nitrate leaching. NLS§ 3.3. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil sample. The perc test results reveal a relatively rapid permeability considering the clay content TABLE I SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS "Ilk MVIE LIPTI'Ii SOIL TEXTURE SOIL NITRATE- pH A.ND CLASSIFICATION NETROGE's C.ON'I ENT CATION ERCITANGE CAPACII'N In meq/100g 38 IN.DEPTH Loam 8 ppm NO-N 7.3 14.8 me /100 Page 2 of 12 �J Chesney Consulting