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• The soil in the borings was similar to that described by the Soil Survey. At location P1, silty, fine to medium sand was encountered to a depth of 2.5 feet, followed by sandy silt. At location P2, fine to medium sand with silt was encountered for the full depth of the hole. The soil logs are presented on Plates 10 and 11. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be good potential for percolation at the test locations. 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 on each proposed parcel of the Site. The soil borings discussed above were used for the percolation test holes (Plate 9). 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 soils logged, the test holes were completed for the percolation tests. Approximately one inch of pea gravel was 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 tests for the borings on July 14, 2017. Due to rapid percolation rates observed, one-hour tests were selected. Water level measurements were taken every 10 minutes during this one-hour period. The tests were observed by Ted Tasiopoulos, Senior 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, the holes were refilled with water • to a level of six inches or more above the bottom of the hole. LOGE 1718 Page 6