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Discussion of Soil Lithology <br /> Based on the soils observed in the borings, there appears to be potential for percolation <br /> in the test locations. Sandy soils generally have a much greater potential for percolation <br /> than fine-grained or cemented soils. However, a percolation test is the only accepted <br /> method for determining the suitability of the soils for a septic disposal area. Percolation <br /> test results are discussed in the following section. <br /> Percolation Test <br /> A percolation test involving shallow and deep holes was conducted on Parcels 1 and 2 <br /> of the Site; a shallow test was conducted on Parcel 3. The soil borings discussed <br /> above were used for the percolation test holes (Plate 2). Percolation test procedures <br /> conformed to San Joaquin County Environmental Health Department policy. <br /> Preparation and Presaturation of Percolation Test Holes <br /> After the borings were advanced by hand auger and the soils logged, the test holes <br /> were completed for the percolation tests. Approximately one inch of pea gravel was <br /> placed in the bottom of each open soil boring, followed by a 1 .5-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 tests. Where necessary, the holes were filled with water to a height of 12 <br /> inches above the bottom of the boring for the presaturation. On the day of testing, all <br /> the holes except the shallow boring on Parcel 2 were found to be intact and dry; that <br /> hole was intact but contained standing water. <br /> Percolation Test Procedure <br /> Live Oak conducted the percolation tests for the borings on June 7, 2011. Due to silty <br /> soils observed, four-hour tests were selected. Water level measurements were taken <br /> every half-hour during this four-hour period. The last half-hour of each test was <br /> observed by Michael Escotto, Senior Registered Environmental Health Specialist at the <br /> San Joaquin County Environmental Health Department. <br /> An electronic well sounder with a depth accuracy of 11100"' foot was utilized for the <br /> water level measurements. The water level was measured against a fixed reference <br /> point on the well casing. Measurements were recorded on the data sheet in decimal <br /> feet. When necessary after measuring the water level, the hole was refilled with water <br /> to a level of six inches or more above the bottom of the hole. <br /> LOGE 1107 Page 6 <br />