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Percolation Test Shallow percolation tests were conducted on Parcel 1 and Parcel 2 of the Site; the soil borings discussed above were used for the percolation test holes (Plate 2). Percolation f� 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. t Live Oak 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 holes were found to be intact and dry. Percolation Test Procedure ;Live Oak conducted the percolation tests for the borings on October 19, 2010. Due to initial percolation rates observed, four-hour tests were 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 tests. 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. 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 mintin or less. For the Site to utilize a standard LOGE11024 Page 6