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k- KLEINFELDER After the first 30 minutes, the drop in water level in test hole #2 was measured in approximate 10-minute intervals (SJCEHD Procedure #3) for the next 30 minutes. The test procedure changed because the prescribed amount of water seeped out of the hole in less than the 30-minute interval. After 30 minutes, procedure #2 was resumed because the seepage slowed enough to allow this procedure. Under the observation of a representative from the SJCEHD, the last 30-minute readings of the four-hour period were used to calculate the percolation rate in minutes per inch. The SJCEHD representative approved the test results for the percolation test hole P-2. A copy of our field percolation test result is attached on Plate 7. (� J On August 28, 2007,,-sample�of groundwater were obtained using clean procedures 3� -r from a well located site. A permit for the well was not on file with SJCEHD. The water sample ained from the well were delivered to a laboratory on ice that ( s� same day using chain-of-custody procedures for DBCP testin We-boring an percolation test holes were located in the field by visual sighting and/or pacing from existing site features; therefore, the locations shown on Plate 2 should be considered approximate. 6. GROUNDWATER Groundwater was not encountered in the soil profile boring drilled for this investigation. Lines of Equal Depth to Groundwater contour maps published in groundwater reports by the San Joaquin County Flood Control and Water Conservation District (1981 to : 1999) show groundwater levels in the project area ranging from about 10 to 20 feet below ground surface. Based on Lines of Equal Elevation of Groundwater contour maps, the groundwater gradient in the project area is generally from east to west. Local gradient variations may occur due to well usage. We understand that the existing well on the property will be used to supply water for the new facility. No new wells are planned. The results of the groundwater a to determine the concentrations of nitrate (N) in the water sampled from t' e on-sit well indicated a non-detectable concentration with a reporting limit of 0.10 mg is nitrate concentration is below the state drinking water standard of 10 mg/l. The results of the groundwater analysis to determine the concentrations of DBCP in the water sampled from the on-site well indicated a non- 611� detectable concentration with a reporting limit of 0.0050 pg/l. Copies of the test results and the chain-of-custody are presented on Plate 8. We do not know of any existing and/or potential groundwater contamination issues in the project vicinity. There are no existing gas stations or dairies adjacent to the property. Seasonal fertilization of the off-site agricultural land, if performed, and other 81538.G011STO713801 October 4,2007 ©2007 Kleinfelder Page 3 of 5