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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 testing. Approximately 2 inches of pea gravel were 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. Live Oak presaturated the percolation test holes approximately 24 hours prior to the percolation testing. Each 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 holes were found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation tests for the borings on March 25, 2016. Due to soil conditions 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 each 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 or more 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 each hole 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 greater than 1.0 minute per inch (min/in) but less than 60 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 greater than 1.0 min/in but less than 30 min/in. For the Site to utilize a standard septic system in this part of the County, a shallow percolation test must demonstrate a satisfactory percolation rate within the proposed septic system disposal field. Details and results of the percolation testing are summarized in the following table. LOGE 1917 Page 7