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rFsoil n to USDA classifications, the Unified Soil Classificati ystem (USCS) de les (also denoted on the Field PercolationTest Form) Ilt loam), and a an clayey siltm). These soil classifications, �ong with pertinent chemical analytical resul areed in Table 2, on Page 5. C (_ W7 c Percolation Testing `� V GL The second physical test to be c nducted as percolation testing in the location of the primary filter b bed, as described: On January 30, two perc test borings of 24 inches and 36 inches in depth were hand-drilled. The shallow, 24 inch boring is representative of percolation/infiltration that willCjr take place at the soil-effluent interface. The 36 inch boring represents percolation of effluent below this interface. A deep boring of 10 to 25 feet was not drilled to determine the underlying strata because it has been documented on the property directly to the west that the underlying gravel strata begins at approximately 8.5 feet below grade. Therefore, a filter bed arrangement,placed as high in elevation as possible will maintain an approximate 6.5 foot thickness of soil between the soil/effluent interface and this gravel strata. Sidewalls of the borings were scored and the loose material removed with a hand auger. Two J inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted into each hole. The test borings were pre-saturated with 12 inches of water, approximately 24 hours 6 before the start of testing. No standing water remained after the pre-soak period. On January 31, / 2006, percolation testing commenced for the two 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. Although EHD Test Procedure#1 could have been run since the six inches of water seeped away after the first 30 minutes, Test Procedure#2 was run to ensure maximum soil saturation conditions under"worst-case scenario' conditions. Test results revea aped ere rates %inites per inch (mpi) for the 24 inch boring an 6 pi for the 36 inch bori onsequenceptable percolation rate demonstrates sufficient percability at these tested depths anrequire that the septic system for this project be engineered to a higher degree. TABLE 1 PERCOLATION TEST RESULTS WITH CORRESPONDING APPLICATION RATES allons/ft'/da 24 INCH DEEP PERC TEST BORING 9.3 n /inch / 0.857 gallons/ft'/day PERCOLATION RATE/APPLICATION RATE 36 INCH DEEP PERC TEST BORING 7.6 min/inch / 0.914 gallons/ftp/day PERCOLATION RATE/APPLICATION RATE Page -4- Chesney Consulting