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• Soil Borings On October 4, 2016, Live Oak excavated a shallow soil boring on Parcel 1 of the Site and shallow and deep soil borings on Parcel 2 of the Site for the purpose of conducting �52J percolation tests. The borings were four inches in diameter, 3.30, 3.45, and 19.70 feet deep, and were excavated by hand auger (Table 2). The locations of the borings are indicated on Plate 9. The soils in the borings were similar to those described by the Soil Survey. At location P1, silty sand was encountered to 1.5 feet, followed by fine sand with silt to the full depth of the boring (3.30 feet). At location P2, sandy silt was encountered to 2.0 feet, s followed by silty sand to a depth of 5.0 feet, sand with silt to a depth of 11.0 feet, sand with clay to a depth of 15.0 feet, and sand with silt to the full depth of the hole (19.7 feet). The soil logs are presented on Plates 10 and 11. Discussion of Soil Lithology Based on the soils observed in the borings, there appears to be good potential for percolation in the shallow soil zone at test location P1 and in the deep soil zone at location P2. Sandy soils generally have a much greater potential for percolation than fine-grained or cemented soils. However, a percolation test is the only accepted method for determining the suitability of the soils for a septic disposal area. Percolation • test results are discussed in the following section. Percolation Test A shallow percolation test was conducted on Parcel 1 of the Site; shallow and deep percolation tests were conducted on Parcel 2 of the Site. The soil borings discussed above were used for the percolation test holes (Plate 9). Percolation test procedures �IP• �� conformed to San Joaquin County Environmental Health Department policy. Preparation and Presaturation of Percolation Test Holes After the borings were advanced by hand auger and the soils logged, the test holes were completed for the percolation testing. Approximately one inch of pea gravel was placed in the bottom of each open soil boring, followed by a 1.5-inch diameter PVC pipe with perforations on the bottom. Pea gravel was then used to backfill a few inches of the annular space. Live Oak presaturated the percolation test holes approximately 24 hours prior to the percolation testing. Each hole was filled with water to a height of 12 inches above the bottom of the boring for the presaturation. On the day of testing, all three holes were found to be intact. The shallow hole on Parcel 1 and the deep hole on Parcel 2 were found to be dry; standing water was present in the shallow hole on Parcel 2. • LOGE 1621 Page 6