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30 July 2019 AdvancedGeo AGE Project No. 19-4772 Environmental Page 7 of 14 6.2. CONSTRUCTION OF PERCOLATION TEST HOLES On 11 July 2019, one boring was advanced for a shallow percolation test(P-1). The boring was advanced using a four-inch diameter hand auger to a depth of 40 inches bsg. The boring was located within the general area of the proposed septic system location. Following borehole advancement, the sides of the boring were scraped, and loose material was removed from the borehole. Once the borehole was cleared of loose material, two inches of fine gravel was added to the bore hole. The borehole was then filled with water to a depth of 12 inches above the gravel at the time of 0845. The test hole was then covered for 24 hours to allow for complete saturation of the borehole. On 23 July 2019, a second boring was advanced approximately 50 feet from P-1 for another percolation test (P-2). The boring was advanced using the same procedures as above and was filled with water to a depth of 12 inches above the gravel at the time of 0830. The test hole was then covered for 24 hours to allow for complete saturation of the borehole. 6.3. DESCRIPTION OF THE PERCOLATION TEST HOLE - POST SOAK On 12 July 2019, boring P-1 was found to be filled with water to the same level as the day before. The borehole was intact and in good condition, but no percolation had occurred in the 24-hour period. On 24 July 2019, 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 12 July 2019, percolation test hole P-1 was found still filled with water after sitting overnight. Percolation test procedure #1 was attempted for the test. However, no percolation was observed following a 30-minute interval and the test was abandoned. The test was observed by the EHD inspector; the Percolation Test Rate Field Sheet is provided in Appendix C. On 24 July 2019, percolation test hole P-2 was dry after sitting overnight. Percolation test procedure #2 was performed by adding water to approximately six inches above the gravel and recording the amount of water remaining in the borehole at 30-minute intervals for a period of four hours. Additional water was added to the boring after each 30-minute interval as required to ensure that approximately six inches of water remained above the gravel. The water level was measured from a fixed reference point at the surface of the boring using a Solinst water level meter. Measurements were recorded at 30-minute intervals for four hours. The final two measurements were observed by the EHD