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B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The United States Department of Agriculture - Soil Conservation Service (USDA-SCS) indicates the on-site soils to consist of Egbert silty clay loam (#153). The soil was tested by A&L Ag Labs and found to be exclusively a clay soil. SSS§ 5.2. The soil investigation and testing began with hand-drilling a 36-inch deep boring in the proposed effluent disposal location. Soil cutting sample composites from this boring were retrieved for chemical and particle size analysis. NLS§ 1.1, 1.2. As the noted on the A&L Laboratory Soil Analysis Reports, chemical analyses of 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. As noted, the organic matter in the soils is low. The nitrate-nitrogen concentration is low at 2 ppm. This concentration reveals a low potential of nitrate contribution from the indigenous soil concentration. Given the fact that the onsite soils were farmed relatively recently, a higher nitrate- nitrogen concentration would have been expected. Consequently, this concentration suggests a high potential for denitrification. 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 alkaline at a pH of 8.2 which may negatively affect ammonium 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 of nitrified ammonium. NLS§ 3.3, SSS§ 5.3. Table 1 below summarizes the chemical and physical subsurface soil characteristics encountered from the soil sample, illustrating the particularly high clay content percentage. TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE LOCATION AND SAMPLE DEPTH SAND, SILT AND CLAY PERCENTAGES SOIL CLASSIFICATION SOIL NITROGEN CONTENT pH AND CATION EXCHANGE CAPACITY DISPOSAL FIELD AREA 30"-36" 26% 31% 42% Clay 2 ppm NO -N 8.2 22.3 meq/100g 3 Chesney Consulting