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VI. SOIL PROFILE AND PERCOLATION TESTS <br /> Three test holes, one on each of the proposed parcels, were excavated to depths of 3.0 <br /> feet. The purpose of the test holes was to determine percolation rates in these areas. For <br /> approximate locations of the test holes, see the Tentative Parcel Map in the Appendix. Holes <br /> were prepared in accordance with County Standards. <br /> Generally the surface soils consisted of a sandy loam. As shallow percolation tests <br /> proved adequate for conventional septic systems, no further soil exploration was necessary. <br /> Three percolation tests were performed in holes varying from 8 inches to 10 inches in <br /> diameter by 36 inches deep. The holes were backfilled with 2 inches of gravel. All holes <br /> were filled with water 24 hours prior to running the test. The test hole for parcel 2 was dry <br /> after the 24 hour presoak period and therefore required a 4 hour test. The final hour of the <br /> test was witnessed by a County Health Official. Test holes on parcels 1 and 3 still contained <br /> water after the presoak period and therefore required half hour tests which were witnessed by a <br /> County Health Official. The percolation rate results are shown below: <br /> Parcel Number Percolation Rate <br /> 1 2 '/2 inches/hr <br /> 2 3 1/2 inches/hr <br /> 3 1 '/2 inches/hr (extrapolated) <br /> The test hole on Parcel 3 was exhibiting a passing percolation rate consistent with the other test <br /> holes. The County Health Official indicated the proximity of the test hole to the existing leach <br /> field was too far and the test was not completed. The rate shown above is based on the <br /> performance of the test hole at that time. <br /> VII. CONCLUSION <br /> Based on the results of the percolation tests and the soil profile, it is Dillon & <br /> Murphy's opinion that the existing homesite and any new homesites resulting from the <br /> proposed parcel split of the subject property are suited for the construction of a typical on site <br /> sewage disposal system. The proposed system, however, should be properly designed and <br /> installed according to the current San Joaquin County criteria, <br /> Based on the depth to ground water in the area, and the size of the proposed parcels, it <br /> is our opinion that the installation of the proposed septic systems, if properly installed, should <br /> not adversely affect the quality of the ground water in the area. <br /> 3 <br />