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SOIL INFORMATION 7) NLS§ 1.1. The UC Davis Soil Web Map indicates the Map Unit to be a Veritas fine sandy loam (#266), with Grangeville, Bisgani, Madera and Tinnen fine sandy loam soils compose the remaining portion of the subject soils. As referenced, two soil samples were retrieved from the 3 ft and 8 ft depths for physical and chemical analyses. The attached texture analysis reveals the underlying soil consists of a sandy loam (USCS = SM, fine sandy silt). The clay content percentage of the shallow soils is 14%, but declines to 8%clay at the 8 ft depth. 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 0.4% and 0.6%at the 3 ft and 8 ft depths. These OM concentrations suggest there is a low potential for future nitrate forming from organic matter, and comparatively low potential for denitrification. 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 which has the potential of retarding effluent 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 NH4 molecules and was measured at 15.5 meq/100 g,which is an average value. This CEC suggests a medium potential for the retention of ammonium molecules that may form for microbial assimilation within the upper soil environment. The CEC decreases to 9.1 meq/100 g at the 8 ft depth representative of the increase in the silt fraction of the soil and a possible decrease in the retention of NH4 molecules. The nitrate-nitrogen concentrations at the two tested depths reveal results of a potentially high degree of denitrification. The NO3-N concentration at the 3 ft depth is 19 ppm,which is relatively high from the use of nitrogen fertilizers in the sample garden area, and decreases in a distance of 5 ft to 2 ppm NO3-N at the 8 ft depth. This indicates a significant denitrification potential of 90%. This denitrification issue is discussed in the Conclusions Section of this report. NLS§3.3. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil sample. Page -2- Chesney Consulting