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ron� is 4 ft deep. Therefore, groundwater.(the water fable) was truly encountered 13 ft below igrade. This boring provided I.) a profile of the underlying soil characteristics, 2.) depth to ' groundwater and 3.) a water table sample, and a soil sample from the capillary fringe at 12 ft. The log of boring illustrates the subsurface soil characteristics encountered: The surface soils to 2 feet consist of a dark brown clay. Below this strata and extending to 4 ft is a lighter brown, silty clay (clay loam) with consistent moisture. From 4 ft to 12 ft, the soil consists of a yellowish brown clay loam with also with a consistent moisture content. At 12 ft is the capillary fringe with the zone of saturation at 13 feet. No rust mottling was observed which would be indicative,, of seasonal soil saturation.. Three soil samples were obtained for analysis. The first sample was retrieved from Parcel I at 42 in. in depth and is referenced as 42-P1 on the SOIL ANALYSIS REPORT. The second sample was taken from Parcel 2, which is currently an alfalfa field, also from 42 in. in depth and is referenced as 42-AL. The third sample was retrieved from the capillary fringe referenced above at 12 ft, and found to have-4 ppm nitrate-nitrogen and:I 111 ppm TKN. The nitrate-nitrogen concentration can be considered very low, while the TKN is on the high side and may be attributable to decomposing organic matter from the alfalfa crop that was in this location several years ago. Particle size analysis (Soil Texture) was done on 42-AL sample and found to have a high clay content at 43%, with equal parts of silt material (42%). The nitrate-nitrogen (NO3-N) concentration for these two samples werea13 ppm.for Parcel T and 5 ppm for the alfalfa field. The area were the Parcel 1 sample had not been in agricultural production for the last ten years. It is theorized that the nitrate-nitrogen content is higher in the Parcel 1 sample due to organic h matter decomposition, which is ultimately liberating nitrate. Accumulation of nitrate is ` occurring since there are no root structures assimilating the nitrate formed. Conversely, the alfalfa root system is not only manufacturing its own nitrogen, it is also taking up soil nitrate, thus accounting for a lower nitrate-nitrogen concentration. f Additional chemistry of these soil samples was also done to analyze several constituents. 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 organic matter in the soil is low, but in sufficient amounts to contribute some nitrate. Since septic effluent is composed predominately of ammonium (NHA the pH, along with the CEC, are significant influences on ammonium molecules. The pH of the soil is somewhat 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 almost 26.0 suggests there is considerable potential for i the retention of ammonium molecules for microbial uptake, and suppression of nitrification (nitrate formation). k 3 `llalfey AB Research