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The soil in the boring was similar to that described by the Soil Survey. Clay was encountered to approximately 2.5 feet below ground surface, followed by sandy silt 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 boring, there appears to be moderate potential for percolation in the shallow 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 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. 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 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 hole approximately 24 hours prior to the percolation testing. The 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 hole was found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation test for the boring on February 25, 2022. Due to the rapid initial percolation rate observed, a one-hour test was selected. Water level measurements were taken every ten minutes during the one-hour period. The last 30 minutes of the test were observed by Frank Girardi, Registered Environmental Health Specialist at the San Joaquin County Environmental Health Department. An electronic well sounder with a depth accuracy of 1/100th foot was utilized for the water level measurements. The water level was measured against a fixed reference point on the well casing. Measurements were recorded on the data sheet in decimal LOGE 2211 Page 6