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NLS§ 1.2. The soil sampTcontent, also tested for chemical analysis. As noted on the attached Soil Analysis Real analyses conducted quantifies several constituents that influence nitrate loading fThe important parameters for nitrate loading assessment are the organic matter, claation exchange capacity(CEC), and the nitrate-nitrogen content of the soil. The organic matter is low at 0.7%. This O.M. concentration suggests there is a low potential for future nitrate forming from organic matter. However, as nitrate molecules that may form percolate downward, these molecules travel through the clayey soil. This soil type is generally anaerobic, thus promoting denitrification and inhibiting nitrification(the formation of nitrate). 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 acidic which may have the effect of promoting ammonium formation and not ammonia formation. Ammonium is the precursor to nitrate formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at 12.3 meq/100 g,which is a medium value. This suggests a medium potential for the retention of ammonium molecules for microbial assimilation within these soils. The nitrate-nitrogen is also a low concentration at 8 ppm, indicating a low potential for continued nitrate leaching. NLS§3.3. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil sample: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DLP I'D SOIL TEXTURE SOIL NI'I'RATF, pH AND CLASSIFICATION NII ROGEN CONTENT C;A'IION EXCHANGE CAPACITY In meq/100g 36 IN.DEPTH Sandy Clay Loam 8 ppm NO-N 6.3 12.3 me /100 GROUNDWATER INFORMATION NLS§ 2.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The Spring 2015 Lines of Equal Depth Maps and the Lines of Equal Elevation Maps indicate groundwater depth and C2 directional flow. Depth to groundwater is approximately 145 ft and groundwater directional flow appears to be in a northwesterly direction. - NLS§ 2.2,3.1. Surrounding properties are currently farmed and have been for decades, so the �Z 2 potential for nitrate contamination of the underlying groundwater can be considered significant. As noted below,the nitrate-nitrogen concentration in the well water is 4 ppm, or almost one-half the �3 I Maximum Contaminant Level (MCL). Pae 1 of 7 Chesney Consulting