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a. kn KLEINFELDER perforated PVC pipe. Before noon on May 17, 2006, aboLlt 12 inc s of water was placed in the hole for pre-soaking. On May 18, 2006, the pi rcolati test was started at about 7:00 AM in accordance with SJCEHD accept% ' elines, 'ng clear potable water. The hole did not exhibit sloughing or caving. The hole wal not mpty Lj of water prior to testing. From a fixed reference point a non he ide of PVC ipe} the drop in water level was measuredapproxima 0- to intervals fo four 'ours} , refilling as necessary to maintain t e prescribed a unt of wa r e i (SJCEHD Procedure #2). Under the bservation of a r Liar from tk Lra v- the SJCEHD, the last 30-minute reading of the fo r-hour period wa� used to calcula per inch. The SJCEHD e the percolation rate in minutes p HD representative approved the C� test results �"or the rcolation test hole P-1. A cop of our field"percolation test result is attached o Plate _ C7 On May 23, 2006, san*es of groundwater were obtained using clean procedures from a spigot at the headof the domestic well located near the existing residence. A permit + I - for the well was not on_file with SJCEHD. The water samples obtained from the well were delivered to a laboratory-on ice that same day using chain-of-custody procedures for DBCP and nitrate (N) testing. The boring and percolation test holes were located in the field by visual sighting and/or Fi pacing from existing site features; therefore, the locations shown on Plate 2 should be considered approximate. 6. GROUNDWATER FtGroundwat was encountered-in the soil profile boring drilled for this investigation at a depth"61f 7 eet below existing site grade. Lines of Equal Depth to Groundwaterr contou s published in groundwater reports by the San Joaquin County Flood L Control and Water Conservation District (1981 to 1999) show groundwater levels in the project area ranging from about 9 to 25 feet below ground surface. Based on L� Lines of Equal Elevation of Groundwater contour maps, the groundwater gradient in ' the project area is generally from the northwest to the southeast. Local gradient F11 variations may occur due to well usage. ° We understand that a new well will be installed on the property and will be used to i supply water for the new facility. We anticipate that the predominant use of groundwater will be for public and landscaping purposes. The results of the groundwater analysis to determine the concentratio - %/1. rate (N) In the water sampnisnot e on-site well indicated a concentration 14 This lY` nitrate concentratiBlow the state drinking water standard of 1 mgli. DBCP was not present i' ,e nts. Copies of the test results and the chain-of- custody are presented or�Plate 8 i 71324.G011ST06R648 June 19,2006 ©2006 Kleinfelder, Inc. Page 3 of 8