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July I7,2002 Job Number: LG02-136 Page 8 The 9-foot exploratory boring was drilled to characterize the shallow soils of the proposed septic disposal field. Generally,the soil encountered in the boring is similar to the soils reported by the San Joaquin County Soil Survey soil for the area. Table 5 presents the soil log for the 9-ft soil boring. Table 5. Soil Boring Log. Depth Interval(ft) Soil Type Unified Soil Classification 0-1 Dark brown sand with/gravel. Sp 1-5 Dark brown silty sand with some clay. SP 5-8 Light brown sandy silt. ML 8-9 Light brown silty sand. Sp The required 3-ft deep (shallow test)percolation test hole was drilled adjacent to the 9-ft r deep soil boring. The sides of the percolation test boring was cleaned with a sharp tool. A 2- inch PVC pipe with several perforations on the bottom of the casing was use to measure the drop of water in the test boring. Approximately 2 inches of"pea gravel'was placed in the bottom of the boring then the PVC casing was installed on the gravel. Several feet of"pea gravel'was backfilled in the annular space. Presaturation of the percolation test hole occurred on April 18, 2002. Measurement of the water level during the percolation test was from a fixed reference point on the PVC casing using an electric well sounder with an depth accuracy of 1/100th foot. All values on the field data sheet are in decimal feet. A 4-hour percolation test was conducted on April 19, 2002 in accordance with the requirements of San Joaquin County Environmental Health Division. The last %2 hour of the test P-1 was observed by Lisa Medina, Environmental Health Specialist, of that office. A satisfactory percolation rate for a shallow(3-foot deep)test is 60 min/in or less. The test achieved a satisfactory percolation rate of 8.9 min/in. A summary of the percolation test is presented on Table 6. Table 6. y Summary of percolation test. Test No., Percolation Percolation Rate Comment Date Tested Test Depth(ft) I (minutes/inch) P-1,4/19/02 3 8.9 Passed percolation test. r Soo >y O A �e oo c.