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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 36 inches and 25 feet; a satisfactory percolation rate for a deep test is greater than or equal to 1 minute per inch (min/in) but less than or equal to 30 min/in drop. For the Site to utilize a standard septic system, one percolation test (shallow or deep) must demonstrate a satisfactory percolation rate within 100 feet of the proposed septic system disposal field. Details and results of the percolation test are summarized in the following table. Table 2. Percolation Test Summary Test No., Percolation Test Percolation Rate Test Duration Comments Date Tested Depth (ft.) (minutes/inch) (see notes) P1, No movement, 6/2/2020 3.36 --- 4 hr. Shallow Test failed P1, Satisfactory perc. 6/2/2020 25.0 12.5 4 hr. rate Deep Test Note: A satisfactory percolation rate for a "shallow" test is greater than 1 but less than or equal to 60 minutes per inch. A satisfactory percolation rate for a "deep" test is greater than 1 but less than or equal to 30 minutes per inch. Only one percolation test (shallow or deep) must demonstrate a satisfactory percolation rate for the area to be considered acceptable for a standard septic system. 1 Per San Joaquin County Environmental Health Department, a rate between 5.0 and 30.0 min/in requires an eight-foot separation between the bottom of dispersal system and ground water, or mitigation by system design or enhancement. Discussion of Percolation Test Results The soils within the proposed sewage disposal area of the Site have demonstrated a satisfactory percolation rate for the use of standard septic systems in accordance with the requirements of the San Joaquin County Environmental Health Department. This percolation test is considered representative of soils within a 100-foot radius of the test location. Because of the percolation rate between 5.0 and 30.0 min/in encountered in the test hole, the San Joaquin County Environmental Health Department will require an eight- foot separation from the bottom of the dispersal system to ground water. Ground water is anticipated to be encountered approximately 120 to 127 feet below ground surface at the Site; consequently, no modifications to standard septic systems should be required. LOGE 20-20 Page 8