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13 August 2019 AdvancedGeo AGE Project No. 19-4782 Environmental Page 7 of 14 5.1. SOIL PROFILE PIT INCLUDING DEPTH AND DIMENSIONS The percolation test hole was located in the disposal field area of the proposed septic system. The percolation test hole was advanced to a depth of 40 inches bsg using a four- inch diameter hand auger (Figure 2). 5.2. SOIL LITHOLOGY AS RELATED TO FUTURE ONSITE SEPTIC USES The soil was visually described in accordance with the Unified Soil Classification System (USCS) by a representative of AGE under the supervision of a California Professional Geologist. The soil collected from the percolation test hole boring consisted of dry silty sand over the entire 40 inches of the borehole. The soil type is considered semi- permeable to permeable and sufficient for Ii uid was7,tte disposal and treatment. 6.0. PERCOLATION TEST INFORMATION V [� A percolation soil suitability test was performed at the site under EHD permit No. SR0080851 using a four-inch diameter soil boring established to a total depth of 40 inches bsg. A site map showing the approximate location of the percolation test hole is illustrated in Figure 2. A precise description of the location and construction of the percolation test hole is included in Appendix D (EHD form 42-03 revised 11/02/2009). The soil suitability study was conducted within the area of the proposed septic system leach field. 6.1. NUMBER OF PERCOLATION TESTS PERFORMED One shallow percolation test was performed at the site. The appropriate percolation test ✓' procedure established by the EHD was followed for the test (Procedure #2). The percolation test hole was pre-soaked overnight for 24-hour followed by a four-hour percolation testing period. 6.2. CONSTRUCTION OF PERCOLATION TEST HOLE On 18 July 2019, one boring was advanced for a shallow percolation test. The boring was advanced using a four-inch diameter hand auger to a depth of 40 inches bsg. The boring was located in the leach field area of the proposed septic system (Figure 2). 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 borehole. The borehole was then filled with water to a depth of approximately 12 inches above the gravel at the time of 0850. The test hole was then covered for 24 hours to allow for complete saturation of the borehole.