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feet, followed by fine to medium sand with silt to the full depth of the hole. The soil log is presented on Plate 10. Discussion of Soil Litho/ogy Based on the soil observed in the boring, there appears to be minimal potential for percolation in the shallow soil zone but good potential for percolation in the deep 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 Shallow and deep percolation tests were conducted in the proposed septic disposal area of the Site. The soil borings discussed above were used for the percolation test holes (Plate 10). 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 soil boring. For the shallow test, a 2.0-inch diameter PVC pipe with perforations on the bottom was placed in the hole, and pea gravel was then used to backfill a few inches of the annular space. For the deep test, approximately two inches of pea gravel and a perforated 4.0-inch PVC pipe were utilized. Live Oak presaturated the percolation test holes approximately 24 hours prior to the percolation testing. The holes were 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. Standing water was noted in both holes; some of this water appears to have been rainwater that seeped into the holes from the surrounding areas. Percolation Test Procedure Live Oak conducted the percolation test for the borings on January 4, 2019. Due to percolation rates observed in the shallow test hole, a four-hour test was selected. Water level measurements were taken every 30 minutes during this four-hour period. The last 30 minutes of the test were observed by Sukhreet Kaur, 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 LOGE 1848 Page 6