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i characteristics, 2.) Evidence of seasonal or past soil saturation, and 3.) An investigation of the water table depth. Both backhoe test pits were excavated to 16 ft in&12th with no_free roundwater encountered. Test pit number one was excavated in the exact location of the proposed leachfield area, as illustrated on the attached Site Plan. As referenced, the subsurface material is a stratification of fine-to-medium sandy silts and silty sands. The log of boring for this first backhoe test pit is found on the FIELD PERCOLATION TEST REPORT and illustrates the subsurface soil characteristics encountered: The surface soils to 1.5 feet consist of a medium brown fine silty sand. Below this strata and extending to the test pit depth of 16 ft is stratification of light brown fine sandy silt, silty sand. Test pit number two was excavated between the proposed leachfield and the proposed Ski Lake. The stratification of test pit number two was similar in soil structure to test pit number one. There was a very distinctive clay stratum at 10 ft below grade and extending for three ft down that is notuite as,distinctive in test it number one. t Rust mottling was observed in the test pits which would be indicative of seasonal soil saturation. Mottling occur from reactions under saturated conditions, organic matter and temperatures above 4 C. Under these conditions, the indigenous bacteria utilize the oxygen present when feeding on If_ the organic matter. When the oxygen is depleted, other bacterial types use oxidized iron (rust) rather than oxygen in their metabolism. A hand boring was drilled to five feet below existing grade in the area of the Sand Beach. No groundwater was encountered. The underlying soil structure consists of a white, poorly graded "sugar" sand of uniform, medium, size characteristics. Two soil samples were obtained from the proposed leachfield (LF) area for chemical analyses, from depths of 4 ft and 9 ft. These two samples are referenced on the SOIL ANALYSIS REPORT as LF4FT and LF9FT, respectively. The primary constituent of concern is the nitrate- nitrogen(NO3-N) concentration of the soil. Both soil sample depths reveal very low (VL) concentrations of nitrate-nitrogen at 4 ppm and 3 ppm, respectively. These concentrations are low considering the land was in agricultural production and will have negligible impact on the underlying groundwater with respect to nitrogen. Additional chemistry of the soil sample was also done to analyze several constituents. The important parameters for nitrate loading assessment are the organic matter, pH, cation exchange capacity (CEC), along with nitrate-nitrogen content. As noted, the organic matter in the soil is low at the 4-ft depth, but medium at the 9-ft depth, which explains the aforementioned rust mottling. This suggests that there is amall� potential for future nitrate-nitrq engu loading originating from the or anic matter. 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 relatively alkaline which may slightly inhibit ammonium formation and stability, and may create a small propensity for ammonia(NH3) formation. The CEC measures the ability of the soil to theoretically trap and hold ammonium molecules. A CEC of 9.5 and 18.6 at the respective depths suggests there is a medium potential for the retention of ammonium molecules for microbial uptake, particularly at the deeper depths and for the suppression of nitrification(nitrate formation). Additionally, this higher clay content soil 3 - Val.Cey AB research