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NLS§ 1.2. 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 2.8%. The ENR is 85 lbs/ac. This OM and ENR concentrations suggest there is aaj1pR2Lmediuni 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 because of the soil micropores, 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 very slightly alkaline at 7.1 which won't have much of an effect in promoting ammonia formation or ammonium formation. Since ammonium is the precursor to nitrate, ammonia(NH,)may be slightly promoted, which may retard ammonium (NH4) formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at 23.9 meq/100 g,which is a high value. This suggests a high potential for the retention of ammonium molecules for microbial assimilation within the soil. The nitrate-nitrogen is a medium concentration at 22 ppm, indicating a medium potential for nitrate leaching,but simultaneously a high potential for denitrification within the high clay content soil. 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 SANIPLE DEPIII SOIL TEXTURE. SOIL NITRATE- pH AND CLASSIFICATION NITROGEN CONTENT CATION EXCHANGE CAPACITY In meq/100g 361N.DEPTH Clay 22 ppm NO -N 7.1 21.2 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 Fall 2016 Lines of Equal Depth Map and the Lines of Equal Elevation Map indicate groundwater depth and directional flow. Depth to groundwater is approximately 60 ft below grade and the groundwater directional flow appears to be in a north-northeasterly direction. NLS§2.2,3.1. Surrounding agricultural properties are currently farmed and have been for decades, and surrounding residential properties are on septic systems so the potential for nitrate contamination of the underlying groundwater can be considered significant. Page 2 of 13