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10 May 2021 Project No. 21-6390 Page 7 of 14 by a one-hour percolation test. The percolation test was terminated after one hour due to a very slow percolation rate. 6.2. CONSTRUCTION OF PERCOLATION TEST HOLE On 21 and 22 April 2021, test holes P-1 through P-3 were advanced for a shallow percolation test. The borings were advanced using a four-inch diameter hand auger to depths of 42 inches bsg (P-1 and P-3) and 36 inches bsg (P-2). Borings P-1 and P-2 were completed for performance of a percolation test. The sides of borings P-1 and P-2 were scraped, and loose material was removed from the boreholes. Once the boreholes were cleared of loose material, two inches of fine gravel was added to the bottom of the boreholes and a two-inch diameter polyvinyl chloride (PVC) casing with 0.020-inch slots was installed in the boreholes to perform the test. Gravel was added to the annulus of the boreholes, between the borehole and the casing. Boring P-1 was filled with water to a depth of 12 inches above the gravel at 0835 on 21 April 2021; and boring P-2 was filled with water to a depth of 12 inches above the gravel at 0855 on 22 April 2021. The test holes were covered for 24 hours to allow for complete saturation of the boreholes. 6.3. DESCRIPTION OF THE PERCOLATION TEST HOLE - POST SOAK On 22 April 2021, boring P-1 was found with approximately eight (8) inches of water remaining in the borehole and a percolation test was not performed. Borings P-2 and P-3 were then advanced in alternate locations within the proposed septic system leach field area and boring P-2 was completed for a percolation test. On 23 April 2021, boring P-2 was found to be completely dry, intact and in good condition. 6.4. PERCOLATION TEST CONFORMED TO SJC POLICY EHD 98-02 The work was performed in accordance with San Joaquin County Division 11 Section 9-1105.2 (d) General Requirements. On 23 April 2021, percolation test procedure #2 was performed at boring P-2 by adding water to approximately six inches above the sand and recording the amount of water remaining in the borehole after 30-minute intervals. The water level was measured from a fixed reference point at the top of the casing using a Solinst water level meter. After the first 30-minute interval, only 0.02 feet of water had percolated, and after the second 30- minute interval 0.03 feet of water had percolated. The percolation test was terminated after one hour at 0900 on 23 April 2021 due to the very slow percolation rate.