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feet below ground surface, followed by a layer of sandy silt from 2.5 to 4.5 feet below ground surface. Mixtures of sandy silt and clay were encountered from 4.5 feet to the Cr- total depth of 9.0 feet below ground surface. The log for the soil borings is presented in Plate 9. Discussion of Soil Uthology Based on the soils observed in the borings, there appears to be moderate potential for percolation. Sandy soils generally have a much greater potential for percolation than fine-grained or cemented soils. However, a percolation test is the only accepted J method for determining the suitability of the soils for a septic disposal area. Percolation test results are discussed in the following section. Percolation Test One shallow percolation test was conducted on the Site; the shallow soil boring discussed above was used for the percolation test hole (Plate 2). Percolation test j 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 shallow test hole was completed for the percolation test. Approximately one inch of pea gravel was placed in the bottom of the 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 hole approximately 24 hours prior to the percolation test. 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 shallow hole was 4) found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation test for the boring on October 20, 2010. Due to initial percolation rates observed, a four-hour test was selected- Water level measurements were taken every half-hour during this four-hour period. Michael Escotto, Senior Registered Environmental Health Specialist at the San Joaquin County Environmental Health Department, observed the last half-hour of the test. An electronic well sounder with a depth accuracy of 11100th 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 above the bottom of the hole. LOGE1025 Page 5