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Preparation and Presaturation of Percolation Test Holes After the boring was advanced by .hand auger and the soils logged, the 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 ground was also moistened from recent heavy rains days earlier. 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 percolation test hole was found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation test for the boring on March 18, 2010. Due to soil conditions, a four-hour test was preferred. 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. i 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 an approximate 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 a percolation rate for the hole based on the J 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 (either a shallow or deep test) must demonstrate a satisfactory percolation rate within the proposed septic system disposal field. Only a shallow percolation test was performed. Details and results of the percolation test are summarized in the following table. LOGE1005 Page 6