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FrFrorn the lack of repair permits, the percolation tests results,the underlying soil structure, and the that flow volumes should be very low and intermittent, a lifespan of 20+years for the proposed TS can be expected, provided necessary maintenance is performed. project site has level terrain; consequently, there is no need to incorporate design considerations for slopes within the effluent disposal area. The primary disposal area and 100% replacement area are to be installed parallel to Grovetree Lane in the middle of a ten ft wide landscape planter area, as illustrated on the Site Plans. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS SSS§ 5.0, NLS§ 1.0. The subsurface soil investigation began on March 24, 2026 in the proposed effluent disposal area as illustrated on the Site Plan in Appendix D. Two percolation test borings were hand-drilled in the locations illustrated. Soil samples for chemical and particle size analyses were obtained from these two borings at 24" and 42" below existing grade. The Sample ID's are referenced below in Table 1. As noted on the Laboratory Soil Analysis Report in Appendix C, soil texture is a sandy loam soil. Chemical analyses of the retrieved soil samples quantify several constituents that influence nitrate loading. The soil organic matter content is relatively low. The nitrate-nitrogen(NO3-N) concentration at the 24" depth was 6.04 ppm,then decreases 39%to 3.7 ppm at the 42" depth. Soil pH is an important factor influencing nitrification and denitrification. In general, denitrification rates increase with increasing pH values. The pH values were alkaline at 7.5 and 7.9. The Cation Exchange Capacities (CEC)were 8.9 and 9.6 which is appropriate for this soil type and possesses a small potential for adsorbing ammonium molecules. The clay content of the soils indicates an adequate percentage of clay to promote anaerobic conditions leading to denitrification and other biochemical processes, including the destruction of bacteria and viruses. The clay content concentrations may be providing conducive conditions to promote denitrification. Table 1 below summarizes the analyzed soil physical and chemical characteristics from the retrieved soil samples: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE I.D. SAND/SILT/CLAY% SOIL NITRATE- pH AND DEPTH SOIL TEXTURE NITROGEN CONTENT CATION EXCHANGE CLASSIFICATION CAPACITY 24" 74% 14% 13% 6.04 ppm NO,-N 7.5 8.9 meq/100g Sandy Loam(SM) 42" 79% 11% 10% 3.7 ppm NO3-N 7.9 9.6 meq/100g FSandy Loam(SM) Page -2- Chesney Engineering, Inc.