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Soil Borings <br /> On February 24 through March 10, 2020, Live Oak excavated shallow and deep soil <br /> borings near the proposed septic disposal area of the Site for the purpose of conducting <br /> a percolation test. The borings were four inches in diameter, 3.39 and 15.17 feet deep, <br /> and were excavated by hand auger (Table 2). The location of the borings is indicated <br /> on Plate 12. <br /> The soil in the borings was similar to that described by the Soil Survey. Sandy clay and <br /> cemented sandy clay were encountered to a depth of six feet below ground surface <br /> (bgs), followed by cemented clayey coarse sand to 10.5 feet bgs, then silty fine to <br /> medium sand to 11 feet, then cemented clayey coarse sand to 13.5 feet bgs, then silty <br /> fine to coarse sand to the full depth of the hole. The soil log is presented on Plate 13. <br /> Discussion of Soil Lithology <br /> Based on the soil observed in the borings, there appears to be limited potential for <br /> percolation in the shallow soil zone, but moderate potential for percolation in the deeper <br /> soil zone. Sandy soils generally have a much greater potential for percolation than fine- <br /> grained or cemented soils. However, a percolation test is the only accepted method for <br /> determining the suitability of the soils for a septic disposal area. Percolation test results <br /> are discussed in the following section. <br /> Percolation Test <br /> A shallow and deep percolation test was conducted near the proposed septic disposal <br /> area of the Site. The soil borings discussed above were used for the percolation test <br /> holes. Percolation test procedures conformed to San Joaquin County Environmental <br /> Health Department policy. <br /> Preparation and Presaturation of Percolation Test Holes <br /> After the borings were advanced by hand auger and the soil logged, the test holes were <br /> completed for the percolation testing. Approximately two inches of pea gravel were <br /> placed in the bottom of each open soil boring, followed by a 2.0-inch diameter PVC pipe <br /> with perforations on the bottom. Pea gravel was then used to backfill a few inches of <br /> the annular space. <br /> Live Oak presaturated the percolation test holes approximately 24 hours prior to the <br /> percolation testing. Each hole was filled with water to a height of 12 inches above the <br /> bottom of the boring for the presaturation. On the day of testing, the holes were found <br /> to be intact and dry. <br /> LOGE 20-10 Page 5 <br />