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Table 1. Selected Properties of On-Site Soils (USDA, 1992) Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank and Map Reaction ability absorption Symbol (in) Classification mmhos/cm pH (in/hr) fields Tujunga 0-22: Loamy sand; SW-SM, <2 6.1-7.3 6.0-20 Severe: loamy sand, SM, SP-SM poor filter 0-2% 22-67: Loamy sand, fine sand, <2 6.1-7.8 6.0-20 slopes, sand, SW-SM, SM, SP- 259 SM Note: The table descriptions do not necessarily reflect site-specific soil properties. See description of the map unit for composition and behavior characteristics of the map unit. Soil Borings On April 30, 2019, Live Oak excavated a shallow soil boring in the proposed septic disposal area of the Site for the purpose of conducting a percolation test. The boring was four inches in diameter, 3.13 feet deep, and was excavated by hand auger (Table 2). The location of the boring is indicated on Plate 12. The soil in the boring was similar to that described by the Soil Survey. Silty, fine sand was encountered to the full depth of the hole. The soil log is presented on Plate 14. Discussion of Soil Lithology Based on the soil observed in the boring, there appears to be good potential for percolation in the shallow soil zone. 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 in the proposed septic disposal area of the Site. The soil boring discussed above was used for the percolation test hole (Plate 13). Percolation test procedures conformed to San Joaquin County Environmental Health Department policy. Preparation and Presaturation of Percolation Test Holes After the boring was advanced by hand auger and the soil logged, the test hole was completed for the percolation testing. Approximately two inches of pea gravel were placed in the bottom of the open soil boring, followed by a 2.0-inch diameter PVC pipe LOGE 1923 Page 5