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The soil in the borings was similar to that described by the Soil Survey. Sandy clay was encountered to one foot below ground surface, followed by clay to four feet, then 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 borings, there appears to be limited potential for percolation in the shallow soil zone, but some potential in the deeper soil. 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 at the test location. 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 by hand auger 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 May 3, 2022. Based on the soil types present, a standard four-hour test was selected. Water level measurements were taken every 30 minutes during the four-hour period. The last 30 minutes of the test were observed by Francisco Garcia Ruiz, 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 feet. When necessary after measuring the water level, each hole was refilled with water to a level of approximately six inches above the bottom of the hole. LOGE 2226 Page 6