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The project site has level terrain, consequently, there is no need to incorporate design considerations for slopes within the effluent disposal area. The disposal area is to be installed near the north property line of the subject property. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The UC Davis Soil Web indicates the effluent disposal area soils to consist of Madera sandy loam (#193), with Jahant, Veritas and Alamo soils. SSS§ 5.2. The surface and subsurface soil investigation began on July 30, 2021. A Mobile B-40 Drill Rig was used to advance three borings: A 23 ft exploratory/perc test boring, a 12 ft perc test boring and a 36 inch perc test boring. NLS§ 1.1, 1.2. Soil samples for chemical and texture (particle size) analyses were retrieved from the 3 ft depth, 12 ft depth and 23 ft depth. As noted on the Laboratory Soil Analysis Report in Appendix C, chemical analyses of the retrieved soil samples quantify 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 percentage in the three samples are all low, which is indicative of central valley soils. The nitrate -nitrogen concentrations reveal a highly interesting change with increasing depth: The 3 ft boring sample had 44 ppm NO3-N; the 12 ft sample, 31 ppm NO3-N; and the 23 ft sample, 2 ppm NO3-N. This is a 96% decrease in soil nitrogen concentration between the 3 ft and 23 ft depths. This decrease illustrates significant denitrification occurring from the application of nitrogen fertilizers. It is to be noted that the exploratory boring was drilled near the almond trees to observe effects from nitrogen fertilization, which became readily discernable. The pH of the soils is alkaline at 12 ft and acidic at the other two sample depths. The CEC ranges between 7 and 9 which would be expected given the soil texture analysis of a sandy loam and loam soil. A larger CEC has a higher potential to adsorb ammonium molecules. The clay content of the soil samples indicates an ample percentage of silt and clay to promote denitrification and biochemical processes, including the destruction of bacteria and viruses. NLS§ 3.3, SSS§ 5.3, 5.4. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil samples: Page -2- Chesney Consulting