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Percolation Test A shallow and deep percolation test was conducted in the proposed septic disposal area of the Site. The soil borings discussed above were used for the percolation test holes. Percolation test procedures conformed to San Joaquin County Environmental Health Department policy. Preparation and Presaturation of Percolation Test Holes After the borings were excavated 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. The percolation test holes were presaturated approximately 24 hours prior to the percolation testing. 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; some standing water remained in both holes. Percolation Test Procedure Live Oak conducted the percolation test for the borings on December 16, 2020. A standard four-hour test was selected. Water level measurements were taken every 30 minutes during the four-hour period. The last 30 minutes of the test were observed by Daria Afonskaia, 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 test holes were refilled with water to a level of approximately 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 Ms. Afonskaia and indicates a percolation rate for each hole based on the least 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 or equal to 1 minute per inch (min/in) but less than or equal to 60 min/in drop. A deep percolation test hole has a depth between 42 inches and 25 feet; a satisfactory percolation rate for a deep test is greater than or equal to 1 LOGE 20-56 Page 6