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The organic matter is low starting at 0.5% from the 3 ft depth and decreasing to 0.3% at the 6 ft depth and 0.2% at the 9 ft depth. This O.M. concentration suggests there is very low potential for future nitrate formation from organic matter. The nitrate -nitrogen concentrations illustrate significant denitrification occurring within the soil profile. At the 3 ft depth the NO3-N concentration is 6 ppm, declines to 4 ppm at 6 ft depth and 3 ppm at the 9 ft depth; a 50% reduction. Considering the sample site location was recently under almond orchard cultivation, nitrogen fertilizer applications were significant. 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/neutral which may have the effect of promoting ammonium formation and not ammonia formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at low levels due to the sand texture. This suggests a low potential for the retention of ammonium molecules for microbial assimilation within the soil. NLS§ 3.3. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil sample: TABLE l SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTH SOIL TEXTURE CLASSIFICATION SOIL NITRATE- NITROGEN CONTENT pH AND CATION EXCHANGE CAPACITY In meq/100g 3 FT DEPTH Loamy Sand 6 ppm NO3-N 6.7 3.4 meq/100g 6 FT DEPTH Loamy Sand 4 ppm NO3-N 6.7 3.5 meq/100g 9 FT DEPTH Sand m 3 p NO; -N 7.1 3.1 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 1983 and 1999 Lines of Equal Depth Maps indicate groundwater depth at a potential 9 ft below grade. Soil observations in the backhoe test pit down to 10 ft did not reveal indicators or soil saturation. However, due to the sandy soil texture encountered, soil mottling within a medium coarse sand would be difficult to discern. NLS§ 2.2, 3.1. Surrounding ag properties are currently farmed and have been for decades, so the potential for nitrate contamination of the underlying groundwater can be considered significant. As noted below, the nitrate -nitrogen concentration in the well water is 15.5 ppm; 5.5 ppm over the Maximum Contaminant Level (MCL). Page -2- Chesney Consulting