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SOIL INFORMATION NLS§ 1.1. The UC Davis Soil Web Map indicates the Map Unit to be a Veritas fine sandy loam (4266), with Grangeville, Bisgani, Madera and Tinnen fine sandy loams soils compose the remaining portions of the subject soils. During the percolation test boring procedure, soil samples were retrieved from the 3 ft, 8 ft and 25 ft depths for physical and chemical analyses. The attached texture analysis reveals the underlying soils consists of a clay loam and sandy clay loam. The clay content percentage of the on-site soils can be considered high enough to promote 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 percentage,pH, cation exchange capacity(CEC),the magnesium/calcium cation saturation percentages, and the nitrate-nitrogen content of the soil. SSS§2.1. The organic matter is low at 1.3% and 1.1% at the 3 ft and 8 ft depths, and decreases to 0.5%at the 25 ft depth. These OM concentrations suggest there is a low potential for future nitrate forming from organic matter, but sufficient for denitrification potential. Since septic effluent is composed predominately of ammonium(NH4),the pH, along with the CEC, have significant influence on ammonium molecules. The magnesium saturation percentage is high in the shallow soils and has the potential of detaining infiltration and percolation. The pH of the soil is alkaline which may have the effect of promoting ammonia formation and not ammonium formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at 27.6 meq/100 g,which is a comparatively high value. This suggests a high potential for the retention of ammonium molecules that may form for microbial assimilation within the soil environment. The nitrate-nitrogen concentrations exhibit interesting results: The NO3-N concentration at the 3 ft depth is 3 ppm, increases to 6 ppm at the 8 ft depth and then decreases to 3 ppm at the 25 ft depth,thus indicating a possible significant denitrification potential. NLS§3.3. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil sample. Page -2- Chesney Consulting