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April 29,2003 Job Number. LG03-103 Page 7 BI and B2 were drilled on Parcel 1. B1 was drilled to three feet, the shallow soils encountered, consisted of brown sandy slit and cobbles. B2 was terminated at 23 feet due to ` auger refusal, before which fine to coarse grained sand with gravel was encountered at a depth of 15 feet. B3 and B4 were drilled on Parcel 2. B3 was drilled to three feet in which sandy clay with cobbles were encountered. Drilling B4 encountered red silty sand and cobbles at a shallow depth and red sandy clay at the terminal depth of 25 feet. Though the soils at this location were evaluated to depth of 25 feet, the percolation test hole was set at 23 feet due to some minor sloughing within the open boring. B5 and B6 were drilled on Parcel 3. B5 was drilled to three feet. The soils ranged from red sandy silty clay with cobbles to reddish brown silty sand with gravel. Drilling B6 encountered red silty sand with cobbles at a shallow depth and dark brown silty sand with gravel at the terminal depth of 25 feet. Though the soils at this location were evaluated to depth of 25 feet, the percolation test hole was set at 23 feet due to some minor sloughing within the open boring. The purpose for drilling shallow and deep percolation test holes on each of the parcels was to ma)dmize the chances that each parcel would achieve a satisfactory percolation tests_ See Plate it 1 for the locations of the percolation tests. For each percolation test boring, two inches of"pea gravel"was placed in the bottom of 6. hole. The casing, a 2-inch PVC pipe with holes drilled in the bottom,was installed, and 2 to 3.5 inches of"pea gravel"was backfilled in the annular space. The percolation holes were pre-soaked and a short preliminary test was conducted on April 9, 2003 to determine whether a 1 hour or 4 �` hour test was required. Based on preliminary tests, 4 hour tests would be conducted. Six 4-hour percolation tests were conducted on April 11, 2003 in accordance with the requirements of San Joaquin County Environmental Health Department. The last 1/2 hour of the test was observed by Mchael Escotto, of that office. The percolation test performed in the deep hole on Parcel 1 resulted in a percolation rate of 19.23 min/in(21-ft depth). The shallow hole on parcel one resulted in the unsatisfactory result of 125 min/in (3-ft depth). The parcel two percolation tests resulted in percolation rates of 125 min/in (3-ft depth) and 83.3 min/in (23-ft depth). The parcel three percolation tests resulted in percolation rates of 83.3 min/in (3-ft depth) and 125 min/in (23-ft depth). A satisfactory percolation rate is 60 min/in or less for a three foot