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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 test. Approximately 2 inches of pea gravel were / 6•S� 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. LOGE presaturated the percolation test holes approximately 24 hours prior to the percolation test. 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 presaturated holes were found to be intact and dry. Percolation Test Procedure LOGE conducted the percolation test for the boring on October 20, 2009. Due to initial percolation rates observed, four-hour tests were required. 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 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 above the bottom of the hole. Percolation Test Results The completed percolation test form is included in Appendix 3 of this report. The form was signed by Mr. Escotto and indicates percolation rates for the holes based on the final water drop observed. Per San Joaquin County Environmental Health Department's definition, a shallow percolation test hole has a depth between 36 and 42 inches; a satisfactory percolation rate for a shallow test is less than or equal to 60 minutes per inch (min/in) drop. A deep percolation test hole has a depth greater than 3.5 up to 25 feet; a satisfactory percolation rate for a deep test is 30 min/in or less. For the Site to utilize a standard septic system, one percolation test must demonstrate a satisfactory percolation rate within the proposed septic system disposal field. Details and results of the percolation tests are summarized in the following table. LOGE0914 Page 6