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Preparation and Presaturation of Percolation Test Holes After the borings were advanced by hand auger and the soil logged, the test holes were completed for the percolation testing. 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 test for the borings on July 13, 2023. Due to initial percolation rates observed, a one-hour test was selected for the shallow boring; a standard four-hour test was selected for the deep boring. Water level measurements were taken every 5 to 10 minutes during the one-hour period, and every 30 minutes during the four-hour period. The last 30 minutes of the test were observed by Naseem Ahmed, 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, each hole was refilled with water to a level approximately six inches above the bottom of the hole. For the shallow hole, although sufficient water was added at each reading to fill the hole to a height of six inches from the bottom, the water flowed away too quickly to allow for measurement at that height. It appears that a horizontal rodent burrow or large crack in the clay soil may have developed overnight, causing water to drain away at the six-inch level. Live Oak was able to conduct the percolation test on the water column below the drain-away point so that an accurate percolation rate could be obtained. Mr. Ahmed requested an additional three readings beyond the typical percolation test length to confirm that the readings were consistent. Percolation Test Results The completed percolation test form is included in Appendix 3 of this report. The form was signed by Mr. Ahmed and indicates a percolation rate for each hole based on the final water drop observed. LOGE 2325 Page 6