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Percolation Tests Shallow percolation tests were conducted on both proposed parcels. The soil borings discussed above were used for the percolation test holes (Plate 9). Percolation 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 two inches of pea gravel were placed in the bottom of each open soil boring, followed by a 2.0-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 holes were found to be intact and dry. Percolation Test Procedure Live Oak conducted the percolation tests for the borings on November 16, 2018. Due to soil conditions observed, one-hour tests were selected. Before starting the one-hour tests, six inches of water were observed to drain completely from each hole in less than 30 minutes, per San Joaquin County Environmental Health Department policy. Water level measurements were taken every 10 minutes during the one-hour period. The last 10 minutes of each test were observed by Jeffrey Wong, Senior Registered Environmental Health Specialist at the San Joaquin County Environmental Health Department. 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 holes were 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. Wong and indicates the 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 minute per inch (min/in) drop but less than or LOGE 1816 Page 6