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The project site has relatively level terrain with a slight decline to the north. There will b]nd ed to incorporate design considerations for slopes within the mound system area since the slopot severe enough. Mound systems are sensitive to sloping, and changes in design must be tto consideration when natural ground sloping is present. This is typically taken to be slopiner than 1%-2%. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESUL The United States Department of Agriculture - Soil Conservation Service (USDA-SCS) is the on-site soils to consist of Egbert silty clay loam (#153). SSS§ . . The surface and subsurface soil investigation and testing began with drilling - and one 36-inch deep boring in the proposed effluent disposal location. An additiongwas drilled to 6.5 ft to determine the water table depth. Soil cutting sample composites fisdeeper boring were retrieved for chemical analysis. NLS§ 1.1, 1.2. A)the noted on the A&L Laboratory Soil Analysis Reports, chemical anaf the soil sample quantify the constituents that influence nitrate loading from this project. The important parameters for nitrate loading assessment are the organic matter, pH, cation exchange capacity (CEC), clay content percentage, along with nitrate-nitrogen content of the soil. These test constituents were also measured to provide a baseline for potential future comparisons of soil samples from under the mound system. As noted,the organic matter in the surface soils is medium. This concentration suggests a medium- to-high potential for future nitrate-nitrogen loading from indigenous nitrogen soil content. Organic matter is needed for denitrification so there is also an average denitrification potential within the soil. The nitrate-nitrogen concentration is low at 5 ppm. This concentration reveals a low potential of nitrate contribution from the indigenous soil concentration. Because septic effluent is composed predominately of ammonium (NH4),the pH, along with the CEC, are significant influences on ammonium molecules. The pH of the soil is slightly alkaline at 7.3 which may have little effect on ammonium formation and stability. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange Capacities of the soil sample is comparatively high due to the clay content. Therefore, there is a larger potential for the �retention �of ammonium molecules for microbial uptake and denitrification potential. NLS§3.3, SSSS.. Table 1 below summarizes the chemical and physical surface and subsurface soil characteristics encountered from the soil sample, illustrating the particularly high clay content percentage. 3 Chesney Consulting