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../ k'q KLEINFELDER O/below existing site grade due to drilling refusal. The borings were drilled using a Simco 2400 truck-mounted drill rig equipped with 6-inch O.D. solid-stem auger. The approximate boring locations are presented on Plate 2. A representative with our firm maintained a log of the borings and visually classified the soils encountered according to the Unified Soil Classification System (see Plate 4). A key to the Log of Borings is presented on Plate 5 and the Logs of Borings are presented on Plates 6 through 9. o /Following completion of the soil profile borings, percolation test holes P-1 through P-8 1I were installed within the proposed parcel areas at depths ranging from approximately 3 to 12 feet below site grade. The approximate percolation test hole locations are presented on Plate 2. Following drilling, the sides of the test holes were scored and significant loose material removed from the bottom of the holes. The percolation test holes were then prepared by first placing about 2 inches of fine gravel at the bottom of the holes and installing a 4-inch diameter, perforated PVC pipe. Before noon on June 8, 2006, about 12 inches of water was placed in the holes for pre-soaking. On June 9, 2006, the percolation tests were started at about 7:30 AM in accordance with SJCEHD a accepted guidelines, using clear potable water. None of the holes exhibited sloughing or caving. The holes all contained 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 1'/2 to 2 hours. The percolation tests were terminated after only two hours because the test holes exhibited very little or no percolation. „-On Wednesday July 19, 2006 percolation test holes P-9 through P-16 were installed within the proposed parcel areas at depths ranging from approximately 3 to 5 feet below site grade. The approximate test hole locations are presented on Plate 2. The 6.y percolation test holes were prepared in the same manner as described above. Before noon on July 19 and 20, 2006, about 12 inches of water was placed in the holes for presoaking. On July 20 and 21, 2006, the percolation tests were started at about 9:00 AM in accordance with SJCEHD accepted guidelines, using clear, potable water. None of the holes exhibited sloughing or caving. The holes all contained water prior to testing. From a fixed reference point (a marked location on the side of PVC pipe), the ,r drop in water level was measured in approximate 30-minute intervals for 4 hours (SJCEHD procedure #2). Under the observation of a representative from the SJCEHD, the last 30-minute reading of the 4-hour period was used to calculate the �. percolation rate in minutes per inch. Copies of our field percolation test results are /On on Plates 10 through 17. �' On June 20, 2006, samples of groundwater were obtained using clean procedures y 5 from a spigot at the head an agricultural well located on adjacent propgrty west of the l'7 ` subject parcels. A permit 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. 1 72113.E01/ST06R813 July 26,2006 ©2006 Kleinfelder, Inc. Page 2 of 6 /