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SSS§ 5.2, NLS§ 1.1, 1.2. As the noted on the A&L Laboratory Soil Analysis Reports, chemical analyses of the two soil samples from the 42-inch depth and the 25-foot depths quantify several 5 } constituents that will 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. As noted, the nitrate-nitrogen content is low at 42 inches and very low at 25 feet deep, with the concentrations being 7 ppm and 4 ppm, respectively. Organic matter in the soil is low in both soil samples, and also decreases with depth. These two analyses suggests a very low potential for future 1 nitrate-nitrogen loading from indigenous nitrogen soil content. It also suggests a medium denitrification potential since the nitrogen concentrations are decreasing with depth. 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 near neutral which may inhibit ammonium fon-nation and therefore stability, thus being detrimental to nitrification. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. Cation Exchange Capacities of the soil samples are medium due to the clay and silt contents. This suggests there is a medium potential for the retention of ammonium molecules for microbial uptake, and suppression of nitrification. SSS§ 5.3 Table 1 below summarizes the subsurface soil characteristics encountered from the 42" and 25 foot depths: TABLE 1 SOIL PROFILE CHARACTERISTICS AND ANALYTICAL TEST RESULTS SAMPLE LOCATION, SAND,SILT AND USDA SOIL SOIL NITROGEN pH AND SAMPLE DEPTH AND CLAY CLASSIFICATION CONTENT CATION EXCHANGE (SAMPLE NUMBER) PERCENTAGES CAPACITY DISPOSAL FIELD 41%, 26%. 33% Clay Loam 7 ppm NO;-N 6.6 1 1.1 megll00g ; .h 42' ,,, — DISPOSAL FIELD 57%,, 22%, 21%, Sandy Clay Loam 4 ppm NO,-N 7.4 12.0 meq/100g 25 FF DF.PTI I C. PERCOLATION TEST RF,SULTS SSS§ 5.2, 6.2, 6.3. To assess and quantify the permeability of the leachfield area, percolation tests 1. were conducted, as depicted on the Site Plan found in Appendix C. The subsurface soil investigation j and testing began on February 15, 2008 by hand-drilling a 36-inch pert test boring and a 42-inch test boring. Since a thin hardpan strata was encountered at the 36 inch depth, the 42 inch boring was drilled. The sidewalls of the shallow borings were scored with a pry-bar. This is a critical procedure and "opens"potentially smeared surfaces. As referenced, a 25 foot depth test depth was drilled with l a truck mounted drill rig but not tested because the entire soil profile was saturated from this winter's rains. 3 Chesney Consulting