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SSS§ 5.2. As detailed in the original Studies completed for the Preston Pipelines project, a deep boring was completed near the subject area to determine subsurface soil characteristics and depth to groundwater. Rust mottling was observed in the test boring at the ten-foot depth indicating seasonal soil saturation. Soil saturation may be beneficial for the promotion of denitrification potential. NLS§ 1.1, 1.2. As noted on the A&L Laboratory Soil Analysis Reports found in Appendix B, chemical analyses of the soil samples from the disposal area quantify several constituents that will influence nitrate loading from this Blue Rhino project. The important parameters for nitrate loading assessment are the organic matter, pH, cation exchange capacity(CEC), clay content percentage, and nitrate-nitrogen content. The organic matter in the soil is low in both samples. However, the nitrate-nitrogen concentrations are medium at the 2-foot depth, but very high at the 42-inch depth. This high nitrate-nitrogen cone ' n may a from the former Hayers Egg Ranch and suggests a very high potential for future nitrate-nitrogenTading from Indigenous nitrogen content within the soil. Since 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 which may inhibit ammonium formation and stability, and may create a propensity for ammonia(NH3) formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange Capacities of the soil samples are medium for the 2-ft depth, but increase significantly at the 42-inch depth. This suggests there is some potential for the retention of ammonium molecules for microbial uptake, and suppression of nitrification. ss5 _< 3 NLS§5:3 Table 1 below summarizes the subsurface soil characteristics encountered from the two sampie-8epths: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE DEPTHFI'%/o,, ND Son, SOIL NITROGEN pH AND CLASSIFICATION CONTENT CATION EXCHANGE S CAPACITY 2 FT DEPTH 59%,24%, 16% Sandy Loam 16 ppm NO,-N 7.8 14.7 meq/100g 42 IN DEPTH % . Loam 59 ppm NO,-N 7.7 27.9 meq/100g C. PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability of the on-site soils, the percolation test boring was completed in the proposed leachfield location as depicted in the Site Plan found in Appendix C. The test depth at 40 inches below existing grade gives a comparatively detailed observation of subsurface permeability from approximately 34 to 40 inches in depth. The test depth can be considered to represent the average permeability throughout the effluent receiving soil profile. L3 Chesney Consulting