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SOIL PROFILE AND PERCOLATION TESTING As noted on the USDA Soil Survey map,the on-site soils consists of Redding gravelly loam(#220). Typically, these soil types are well drained with a slow permeability, which can be a beneficial soil attribute for septic effluent management in shallow groundwater areas. However, in this area, slow j permeability in the shallow soils is best managed by seepage pits. As discussed below, only two of the four shallow perc test borings had acceptable percolation, in which both were one-half of the maximum rate allowed. The maximum acceptable perc rate is 60 min/in. A Log of Boring designating the Unified Soil Classification System (USCS) soil classifications as observed from a 25-foot boring completed in the center of the project is found in Appendix C. Logs of boring for each individual test boring are found on the respective EHD PERCOLATION TEST DATA SHEET. Generally, the soils show variability on the surface with a sandy clay at the east 3� end of Parcel 1 to a fine sandy, clayey silt at the east side of Parcel 4. Below five feet, the soils are generally a clayey/silty gravel. Soils from 15 feet to 25 feet in depth consist of a lean/fat clay soil structure. Consequently, the percolation tests were all set within the clayey/silty gravel strata where permeability was more favorable. Located in Appendix B, are five Well Logs of domestic wells drilled in the area, including the on- site well on the subject property. The on-site Well Log shows "rocks"to 20 feet, then brown clay �) from 20 to 32 feet. The depth that water was first found was 128 feet in July of 1975, which correlates with the current water table depth of 130 feet. Percolation testing was conducted on each proposed Parcel in the"back" toward the eastern property border. This assumes the wells for each parcel can be placed in the northwestern area of each parcel since there is no development north of proposed Parcels 2, 3 and 4. The locations of the l tests are measured and illustrated on the Tentative Map. The following information describes the b't� preparation of the percolation test borings and the actual perc testing: On July 15, 2004, one shallow perc test of approximately 42 inches and one deeper test varying from 8 to 13 feet were drilled on proposed lots 1, 2, 3 and 4 in the areas referenced above. The sidewalls of the shallow borings were scored with a pry-bar and the loose material removed. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted. All the test borings were pre-saturated on July 18, 2004 with 12 inches of water, approximately 24 hours before the start of testing. On July 19, 2004,percolation testing commenced for all eight borings. There was standing water in all four perc tests that failed, as depicted in the Table below. Consequently, Perc Test sf) Procedure#1 was conducted for these borings. There was no standing water after the 24-hour soak period in the four test borings with passing rates. Therefore,Percolation Test Procedure#2 was performed. The passing perc rates exhibited average percolation for all four parcels. The (r� last half hour of the tests were witnessed by Lisa Medina of the San Joaquin County (GG) Environmental Health Department. Pae -2- Chesney Consulting