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u � FFand uents listed above also play a role in the denitrification capacity of the underlying soil, the results of this Study and previous domestic well water tests conducted by EHD, e significant. Denitrification capacity is predominately dependant upon: 1.)Abundance ic carbon substrate, 2.)High soil moisture content leading to an anaerobic environment, h soil pH (alkaline). The organic matter content of the subsurface soils are of a low percentage which was to be expected; however, the pH is alkaline for all of the soil samples. During the drilling procedures of the exploratory borings,very moist-to-wet soil moisture conditions were observed, thus creating the potential for an anaerobic environment. This high soil moisture condition can be attributed to the high amount of rainfall during the winter of 2004/2005. NLS§1.2 In addition to the analytical chemistry completed on the soil samples, Particle Size Analysis was also done on the exploratory samples as denoted on the Soil Analysis Reports. These soils have been classified by A&L Laboratory under the United States Department of Agriculture - Natural Resources Conservation Service(USDA-NRCS) classification(e.g., sandy loam, loam, etc.). The Unified Soil Classification System(USCS - e.g., lean clay, silty clay CL-ML/CL) has been used on each of the EHD Percolation Test Rate Field Forms to identify the soil as encountered in the percolation test borings for each individual Lot. Nitrogen in septic tank effluent consists of approximately 75%N in the ammonium ion (NH4') form and 25%N in the organic form. If the ammonium ion is bound and eventually utilized by microorganisms, nitrification cannot occur. The pH, along with the Cation Exchange Capacity (CEC),have significant influence on ammonium. The CEC measures the ability of the soil to theoretically trap, hold and convert ammonium molecules. Soil profiles from both borings have a medium CEC of approximately 15,which should slightly increase the retention of ammonium molecules for microbial uptake and suppression of nitrification. The test results for the important constituents contributing to nitrate formation are tabulated and summarized in Table 1 below. hl addition,the soil texture descriptions from each sample depth are also denoted for comparison purposes. SSS§ 5.2, 5.3, 5.4 TABLE 1 SELECTED SOIL PROFILE DATA UNDER FALLOW LAND AREA OF PROPOSED LOT 3 and LOT 10 110111111 Soil Sample Depth Nitrate-Nitrogen Soil Soil Description and Location Concentration pH/CEC Texture 5 it 3 ppm 8.6/15.7 57%Sand Under Proposed Lot 3 22%Silt Sandy Clay Loam Sample 113;5FT-3 20%Clay loft 3 ppm 8.5/10.5 37%Sand Under Proposed Lot 3 34%Silt Clay Loam Sample m: l OFT3 28%Clay 15 ft 4 ppm 8.5/14.2 69%Sand Under Proposed Lot 3 18%Silt Sandv Loam Sample m:15FT3 12%Clay Page-3- Chesney Consulting