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Percolation Test f A percolation test involving shallow and deep holes was conducted on each parcel of the Site; the soil borings discussed above were used for the percolation test holes (Plate 2). Percolation test procedures conformed to San Joaquin County Environmental (&.J 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. !rave 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 deep holes were found to be intact and dry, while standing water was encountered in the shallow holes. Percolation Test Procedure :Live Oak conducted the percolation tests for the borings on July 28, 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 1/10& 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 forms are included in Appendix 3 of this report. The forms were signed by Mr. Escotto and indicate 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 LOGE1017 Page g