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F L SUITABILITY STUDY ounding and On-site Septic System Information s made of Application Permits on microfiche file with the Environmental Health Department for the study area consisting of the 4000 block of Mariposa Road and the 4000 block of Carpenter Road. The records reveal there has been 11 Application for Repairs/Additions to septic systems within the half-mile radius study area. This can be considered a high number of Repairs/Additions/Replacements considering that seepage pits have been installed in this area to manage the majority of septic effluent flows. B. Percolation Test Results: Soil analysis was conducted on samples retrieved from the east percolation test boring. This boring was drilled near a small metal building at the eastern edge of the property. The Unified Soil Classification System describes the surface soil samples (also denoted on the Field Percolation Test Form) as a lean clay(CL), and a fat clay(CH),with high organic matter. The underlying soils are a silt (loam) (ML), and a lean clayey silt(clay loam) (MLJCL). These soil classifications are summarized in Table 2, Page 4. The second physical test to be conducted was a percolation test in the two denoted locations. location of the primary filter bed, as described: On May 25, 2005, one shallow perc test boring and one deeper boring were drilled with a 12-inch diameter auger connected to a Bobcat tractor. The deeper borings were drilled to 105 inches for the east boring and 95 inches for the north boring. Sidewalls of the 42 inch borings were scored with a pry-bar and the loose material removed with a hand auger. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted into each hole. This test boring was pre-saturated with approximately 12 inches of water, the day before the start of testing. No standing water remained after the pre-soak period for all of the test borings except the shallow east boring,which had approximately 3 inches of standing water. On May 26,2005,percolation testing commenced for all four test borings. The test borings were refilled to approximately six inches of head water and the percolation tests were conducted over a four-hour period to induce maximum soil saturation. EHD Test Procedure#2 was run to ensure maximum soil saturation under`worst-case scenario'conditions. Test results reveal a rapid perc rate of 12.5 minutes per inch (mpi) for the 95-inch deep north boring. The shallow north boring and the deep east boring had comparatively slow perc rates. Table I below illustrates the percolation test rates and related data: Page -3- Chesney Consulting