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1 KLEINFELDER `I EXPECT MORE' Following completion of the soil profile boring, percolation test holes P-1 'P 2 ere drilled within the proposed leach field area at depths of about '/z 31,/)2febel site grade. The approximate percolation test hole locations are-pr�ent�d fate 2. - Following drilling, the sides of the test hole was scored, and significant loos materi l was removed from the bottom of the hole. The percolation test holes were then prepared by first placing about 2 inches of fine gravel at the bottom of the hole and installing a 4-inch diameter, perforated PVC pipe. Before noon on December 28, 2006, about 12 inches of water was placed in the holes for pre-soaking. On December 29, 2006, the percolation tests were started at about 8:40 AM in accordance with SJCEHD accepted guidelines, using clear potable water. The holes did not exhibit sloughing or caving. The holes were not empty of water prior to testing. From a fixed reference point (a marked location on the side of PVC pipe), the drop in water level was measured in approximate 30-minute intervals for four hours (SJCEHD Procedure #2), refilling as necessary to maintain the prescribed amount of water over the gravel. t Under the observation of a representative from the SJCEHD, the last 30-minute reading of the test was observed and the percolation rate, in minutes per inch, was calculated. Copies of our field percolation test results are attached on Plate 7. On January 15, 2007, samples of groundwater were obtained using clean procedures from a spigot at the head of the domestic well located near the existing residence. A / permit for th"ell was on file with SJCEHD. The water samples obtainerfrom,-the / well were delivered /to a laboratM o ice the next day using cliam=of-custody procedures for DBCP and nitrate (N) testin � 7 The boring and percolation test hole xe located in the field by vis s ting and/or pacing from existing site features; therefore, the locations shown on date 2 should be considered approximate. E 6. GROUNDWATER Ground at as encountered in e soil profile boring drilled for this investigation at a depth if 3/Q f et below�xisfi—ng site grade. Based on our experience in the project area, round titer .levels may be in the range of about 6 to 10 feet below ground surface.- ines of Equal Elevation of Groundwater contour maps, published in groundwater reports by the San Joaquin County Flood Control and Water -: Conservation District (1976 to 1992) show the groundwater gradient in the project area is generally to the north to northeast. Local gradient variations may occur due to well usage. �. We understand that the existing well located on the property will be used to supply f water for the church. We anticipate that the predominant use of groundwater will be -� for public and landscaping purposes. _j I 78311.G0115T07R193 March 5,2007 l ©2007 KleWelder, Inc. Page 3 of 8