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by gravel with silty sand to a depth of 16 feet, followed by sand to the full depth of the boring. The logs for the soil borings are presented in Plates 11 and 12. Discussion of Soil Lithology Based on the soil observed in the borings, there appears to be poor potential for percolation in the shallow soil zones but good potential for percolation in the deep soil zones 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 Shallow and deep percolation tests were conducted on both proposed parcels 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 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 1.5-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 tests. 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, both deep holes were found to be intact and dry; the shallow holes were intact, but standing water was present. Percolation Test Procedure Live Oak conducted the percolation tests for the borings on July 10, 2014. Due to soil conditions observed, four-hour tests were selected. Water level measurements were taken every 30 minutes during this four-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 hole was refilled with water to a level of six inches or more above the bottom of the hole. LOGE 1415 Page 6