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The UC Davis SoilWeb Map indicates the Map Unit is a Sailboat silt loam soil type (#234). As referenced, a soil sample was retrieved for physical and chemical analyses. The attached texture analysis reveals the on-site soils at the three-ft depth consists of ai=sand, and clay ercentages of 27%, 50%and 23%respectively. The clay content of the on-site soils can be considered highly significant. 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, clay content,pH, cation exchange capacity(CEC), and the nitrate-nitrogen content of the soil. The organic matter is surprisingly high at 2.6%. This organic matter(O.M.) concentration suggests there is potential for future nitrate forming from organic matter, and simultaneously providing a food source for denitrifying bacteria. The clay soil provides an anaerobic environment 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 slightly acidic which may have the effect of promoting ammonium formation and stability. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules and was measured at 14.2 meq/100 g, which is a medium-to-high value. This suggests a medium-to- high potential for the retention of ammonium molecules for microbial assimilation. The nitrate- nitrogen is low at 5 ppm, indicating a low potential for existing nitrate leaching. 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 SOIL TEXTURE SOIL NITRATE- pH AND CLASSIFICATION NITROGEN CONTENT CATION EXCHANGE CAPACITY In megl1009 36 IN.DEPTH I Sailboat Silt Loam / 5 ppm NO;-N 6.7 14.2 me /100 PERCOLATIO SULTS To assess the permeability at the prescribed depths of the native soils, a percolation test boring was completed adjacent to the excavated Chamber leachlines. After drilling the test boring,the sidewalls were scored with a pry-bar to open potentially smeared sidewalls. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in the test boring. After the drilling procedures,the boring was pre-saturated with 12 inches of water -24 hrs prior to the start of testing. Page 2 of 13 Chesney Consulting