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Percolation Test <br />A shallow and deep percolation test was conducted in the proposed septic disposal <br />area of the Site; due to inconsistent percolation rates in the deep boring, a second deep <br />test was then conducted in the same boring at a few feet greater depth. The soil <br />borings discussed above were used for the percolation test holes. Percolation test <br />procedures conformed to San Joaquin County Environmental Health Department policy. <br />Preparation and Presaturation of Percolation Test Holes <br />After the borings were excavated and the soil logged, the test holes were completed for <br />the percolation testing. Approximately two inches of pea gravel were placed in the <br />bottom of each open soil boring, followed by a 2.0-inch diameter PVC pipe with <br />perforations on the bottom. Pea gravel was then used to backfill a few inches of the <br />annular space. <br />The percolation test holes were presaturated approximately 24 hours prior to the <br />percolation testing. The holes were filled with water to a height of 12 inches above the <br />bottom of the boring for the presaturation. On the day of testing, the holes were found <br />to be intact and dry. <br />Percolation Test Procedure <br />Live Oak conducted the percolation tests for the borings on January 19 and 21, 2020. <br />Four-hour tests were selected for the shallow test and the second deep test; the first <br />deep test was run as a one-hour test. Water level measurements were taken every 30 <br />minutes during the four-hour period, and every five to ten minutes during the one-hour <br />period. The last 30 minutes of each test were observed by Dana Afonskaia, Registered <br />Environmental Health Specialist at the San Joaquin County Environmental Health <br />Department. <br />An electronic well sounder with a depth accuracy of 1/100th foot was utilized for the <br />water level measurements. The water level was measured against a fixed reference <br />point on the well casing. Measurements were recorded on the data sheet in decimal <br />feet. When necessary after measuring the water level, the test holes were refilled with <br />water to a level of approximately six inches above the bottom of the hole. <br />Percolation Test Results <br />The completed percolation test forms are included in Appendix 3 of this report. The <br />forms were signed by Ms. Afonskaia and indicate percolation rates for each hole based <br />on the least water drop observed. <br />LOGE 20-59 Page 6