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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 medium at 2.6%. The ENR is 81 lbs/ac. This OM and ENR concentrations suggest there is an upper 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, 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 21.2 meq/100 g,which is a high value. This suggests a high potential for the retention of ammonium molecules that may form for microbial assimilation within the soil. The nitrate-nitrogen is a medium concentration at 18 ppm, indicating a medium potential for nitrate leaching, but simultaneously a high potential for denitrification within the high claycontent soil. NLS§ 3.3. X 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 DEPTH SOILTERTORE SOILNITRATE- pli AND CLASSIFICATION NITROGEN CONTENT CAI ION EXCHANGE CAPACITY In meq/100g 36 IN. DEPTH Clav loam 1 18 ppm NQ-N 7.4 21.2 me /1000 GROUNDWATER INFORMATION NLS§ 2.1.�roundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The Fall 2016 Lines of Equal Depth Maps and the Lines of Equal Elevation Maps indicate groundwater depth and directional flow. Depth to groundwater is approximateV50 A below-grad6and the groundwater directional flow appears to be in a northeasterly direction. NLS§ 2.2,3.1. Surrounding agricultural properties are currently farmed and have been for decades, and surrounding properties have been on septic systems so the potential for nitrate -- contamination of the underlying groundwater can be considered significant. Page 2 of 12