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April 17, 2019 <br /> BGG Job No. G001.05 <br /> TP-A-3 feet deep (Silty Sand) <br /> Elapsed Time Test Duration Water Level Water Level Drop Percolation Rate <br /> min:sec min:sec inches inches in/hour <br /> 0 0 7.1 <br /> 2:11 2:11 6.9 0.2 5.5 <br /> 4:28 2:17 6.7 0.2 5.3 <br /> 6:45 2:17 6.5 0.2 5.3 <br /> 8:59 2:14 6.3 0.2 5.4 <br /> 11:21 2:22 6.1 0.2 5.1 <br /> 13:40 2:19 5.9 0.2 5.2 <br /> 15:59 2:19 5.7 0.2 5.2 <br /> 18:17 2:18 5.5 0.2 5.2 <br /> 20:38 2:21 5.3 0.2 5.1 <br /> 22:57 2:19 5.1 0.2 5.2 <br /> 45:36 22:39 3.1 2.0 5.3 <br /> 67:48 22:12 1.2 1.9 5.1 <br /> The following is a summary of the percolation rates obtained for the soils encountered at the <br /> specified depths in our recent and previous test pits at Delicato Winery: <br /> SUMMARY OF FIELD PERCOLATION RATES <br /> Test Test Test Depth Percolation <br /> Location Date ft Soil Type at Test Depth Rate min/in <br /> TP-A 1/24/19 3 feet Silty Sand (SM) 11.5 <br /> TP-1 2017 5 feet Sand to Silty Sand (SP/SM) > 60 <br /> TP-1 2017 6 feet Sand to Silty Sand SP/SM 8.0 <br /> TP-2 2017 7 feet Sand to Silty Sand SP/SM 10.0 <br /> TP-3 2017 5 feet Silty Sand SM 12.0 <br /> TP-4 2017 4'/2 feet Silty Sand,HARDPAN SM 60 <br /> TP-4 2017 7 feet Sand to Silty Sand SP/SM 10.0 <br /> TP-5 2017 7%2 feet Silty Sand SM 12.0 <br /> TP-7 2017 7 feet Sand to Silty Sand SP/SM 10.0 <br /> SJC EHD defines a shallow percolation test hole as having a depth between 36 and 42 inches; a <br /> satisfactory percolation rate for a shallow test is one resulting in a water level drop greater than or <br /> equal to 1 minute per inch (min/in) but less than or equal to 60 min/in. For the site to utilize a <br /> standard septic system,one percolation test must demonstrate a satisfactory percolation rate within <br /> the proposed septic system disposal field. If rapid percolation occurs, a separation of 20-feet is <br /> required between the bottom elevation of the dispersal system and the ground water table;otherwise, <br /> mitigation by system design or enhancement is required, per SJC EHD. <br /> Discussion of Percolation Test Results <br /> The soils within the proposed septic system leach field area have demonstrated satisfactory <br /> percolation rates for the use of a standard septic system in accordance with the requirements of the <br /> SJC EHD. Due to the percolation rate recorded,the SJC EHD will require a 20-foot separation from <br /> BAEZ GEOTECHNICAL GROUP Soil Suitability Study and Nitrate Loading Study-DFV Guard Station Page 5 <br />