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I (§ 3.4) The subject property is in an area designated as "High Water Table"by EHD's colored map denoting the various soil types and septic system requirements throughout San Joaquin County. Consequently, only leachlines or filter beds are allowed to be installed in this area of the County. (§ 5.1 and 6.0) SOIL PROFILE AND PERCOLATION TESTING (§ 5.4) As noted on the USDA Soil Survey map, the on-site soils consist of Grangeville fine sandy loam, #166. Typically, this soil type is moderately well-drained due to the levee system, with moderately rapid permeability at depths below 12 inches. As discussed below, the shallow perc test for Parcel 1 had an excellent percolation rate. (§ 5.2, 5.3, and 5.4) A Log of Boring using the Unified Soil Classification System (USCS), and the United States Department of Agriculture (USDA) as observed from the 36-inch deep perc test boring is found on the EHD PERCOLATION TEST DATA SHEETS. Generally, the soils show a clayey, silty soil on the surface, then a consistent silty sand soil under the surface layer down to three feet. Soil characteristics were also determined by a particle size analysis conducted by A & L labs on the soil from the 36 inch depth. The soil is classified(USDA) as a sandy loam: 63% sand, 26% silt and 11% clay. (§ 6.1)Percolation testing was conducted near the end of the existing southernmost leachline, as illustrated on the Site Schematic and Tentative Lot Line Adjustment Map found in Appendix B. This test location was decided upon because effluent typically travels the length of the perforated pipe before depositing out the end. As the biomat develops, or as the soil becomes saturated, the effluent then trickles from the perforations further up the pipe. (§ 6.2, 6.3 and 6.5) On January 25, 2006, 1400 hrs, one shallow pere test boring of 36 inches was hand-drilled. The sidewalls of the boring 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 in the test boring. The boring was pre-saturated on January 29, 2006 at 1100 hrs with 12 inches of water. (§ 6.4) On January 30, 2006, 0800 hrs,percolation testing commenced. There was no standing water after the 24-hour soak period in the shallow perc tests boring, as illustrated in Table 1 below. Consequently, EHD Perc Test Procedure#2 was conducted for this test. The last half hour of the four-hour test was witnessed by Ted Tasiopoulos, R.E.H.S. of the San Joaquin County Environmental Health Department. Perc test results reveal a rate of 7.1 minutes/inch (min/in). The maximum acceptable perc rate is 60 min/in for shallow perc tests. (§ 5.4 and 6.8) The following Table illustrates the proposed Parcel number, septic system structure based on depth of the passing perc rate, proposed acreage, soil characteristics,post soak period status and perc test results for the respective perc test depth: Page -2 _J/ - Chesney Consulting