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The soil in the borings was similar to that described by the Soil Survey. Sandy silt was encountered to approximately 1.0 feet below ground surface, followed by cemented silty sand to approximately 2.5 feet, clayey coarse sand to 9.0 feet, cemented sandy silt to 10.0 feet, sandy silt with clay to 11 feet, and silty fine sand to the full depth of the hole. The soil log is presented on Plate 11. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be limited potential for percolation in the shallow soil zone, but good potential for percolation in the deeper soil zone at the test location. 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 and deep percolation test was conducted in the proposed septic disposal area of the Site. The soil borings discussed above were used for the percolation test holes. Percolation test procedures conformed to San Joaquin County Environmental Health Department policy. Preparation and Presaturation of Percolation Test Holes After the borings were advanced and the soil logged, the test holes were completed for the percolation testing. Approximately two inches of pea gravel were placed in the bottom of each open soil boring, followed by a 2.0 -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, the holes were found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation test for the borings on September 24, 2021. Due to initial percolation rates observed, a four-hour test was selected for the shallow boring, and a one-hour test was selected for the deep boring. Water level measurements were taken every 30 minutes during the four-hour period and every 10 minutes during the one-hour test. The last 30 minutes of the testing were observed by Francisco Garcia Ruiz, Registered Environmental Health Specialist at the San Joaquin County Environmental Health Department. LOGE 2147 Page 6