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rFon rdance with the request of the Environmental Health Department, two backhoe test pits ug near the large filter beds in the SWC of Greenwood and McCracken, and are illustrated Site Plan. The firsttest pit was dug northeast of the filter bed which was assumed to be radient of the filter bed. The second test pit was dug southwest of the filter bed, which wasconsidered upgradient. As illustrated on the SOIL ANALYSIS REPORT form, a soil sample was retrieved from the downgradient test pit at 12 feet below grade and is referenced on the form as 'DN-12." An upgradient sample was retrieved at 8 feet below grade and is referenced as "UP-8." The test results reveal low nitrate-nitrogen (NO3-N) concentrations of 5 ppm and 6 ppm for the 12 and 8 foot depths, respectively. Considering these nitrate-nitrogen test results came from soil under agricultural production land indicate that there has been a relatively low concentration of nitrate-nitrogen that has leached through the soil profile down to this depth. It further shows that based upon this soil analysis (vs. vadose zone water analysis) nitrate leaching should not theoretically affect the water table to a significant extent. The water table chemistry will be discussed below in the Groundwater Information Section of this report. Percolation testing was conducted on the west side of the aforementioned filter beds. Since the soil is uniform throughout the entire subject parcel, this location theoretically gave the best data for future percolation of septic effluent. One shallow perc test of 42 inches in depth was conducted. Typically, in areas of clay soil or hardpan, deeper tests of 8 to 10 feet for sump testing, or a deep test of 25 feet, representative of seepage pits is done. However, since the groundwater is shallow, deeper perc tests were not done. The boring was hand-drilled, scarified and pre-saturated on February 21, 2002, the day before testing. Scarification of the boring sidewalls was extremely important. Readings were taken over a four-hour test period to ensure maximum soil saturation under "worst-case scenario" conditions. The perc test exhibited a medium percolation rate given the clay soil type at 25 minutes per inch. Pere rates similar to the rate obtained have been observed before in this soil type. As can be noted from the water drop every one-half hour, the perc rate did not decrease over the four-hour test. Although the permeability can be considered medium, the soil has a propensity to accept water over time. This may be attributable to the porosity and current moisture content within the soil structure. In addition to the conventional perc test described above, a hydraulic conductivity test of the shallow soil from zero to 18 inches in depth was conducted. This was done to measure the permeability of the surface soils to accept effluent from a filter bed, or shallow leachfield. After four hours of testing, the surface soils absorbed 3,600 cc/hr. This is equivalent to 0.016 gal/min or 23.0 gallons/day. Since the internal area of a 18-inch deep x 4.5 inch dia. boring is 255 int or 1.8 ft',the application rate for the surface soils is theoretically 12.8 gallons/ft2/day. Page -3- Ch mq Consulting