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March 18, 2004 NOA Project Number: LE03-467 Page 2 Soils The drilling of the percolation test holes occurred in Late December 2003 and Early January 2004, between rain storms. The site was wet and inaccessible until March due to heavy rain fall and possibly a broken irrigation pipe which was repaired nearby the percolation test holes. The condition of the holes were affected by mud from the standing surface water. For that reason, P- 4 was drilled on March 16, 2004. The soils encountered during the drilling of P-4 are presented in the following table and are representative of the soils within the proposed septic system disposal field. Soil Log of P-4 Auger Depth Soil Description(Unified Soil Classification System) 0-5 ft Dark brown sandy clay/clayey sand(CL/SC). 5-10 ft Brown silty sand with some clay(SP). 10-20 ft Light brown silty sand,cemented(SP). 20-25 ft Light brown fine sand with silt(SP). Boring Preparation and Specifications The four percolation test borings were drilled with both a 4-inch and 6-inch truck mounted auger drill. A 2-inch diameter PVC pipe with perforations on the bottom was used to measure the drop of water in the percolation test boring. Approximately 2 inches of"pea gravel" were placed in the bottom of the boring, then the PVC pipe was installed on top of the gravel. Several feet of "pea gravel" were backfilled in the annular space. The percolation test dimensions are shown on the percolation test field sheets. Presaturation of Borings Pre-saturation of the percolation test holes occurred on March 15 and March 16, 2004. The depth of water used to pre-soak was 12 inches above the bottom of the borings. After the 24-hour soak period, the pre-saturated holes were found to be intact and dry on March 16 and March 17, 2004. Percolation Test Procedure and Results Three 4-hour percolation tests were conducted on March 16, 2004 in accordance with the requirements of San Joaquin County Environmental Health Division. A forth one-hour test was