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1 KLE/NFELOER \` enynrvopi.wynr somxoM ' 6 FIELD INVESTIGATION ' In order to evaluate the subsurface conditions at the project site, on April 8, 2016, one soil profile borings was drilled within the proposed leach field area to a depth of about 10 feet below existing ' site grade. The boring was drilled using a CME 75 truck-mounted drill rig equipped with 6-inch O.D. solid-stem auger. The approximate boring location is presented on Figure 2. A representative with our firm maintained a log of the boring and visually classified the soils ' encountered according to the Unified Soil Classification System (see Figure 5). A Soil Description Key is presented on Figure 6, and the Boring Log is presented on Figure 7. Following completion of the soil profile boring, percolation test holes P-1 and P-2 were drilled ' within the proposed leach field area to depths of about 3 and 5 feet below site grade. The approximate percolation test hole locations are presented on Figure 2. Following drilling,the sides ' of the test holes were scored, and significant loose material was 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 10:00 AM ' on April 11, 2016, about 12 inches of water was placed in the holes for pre-soaking. On April 12, 2016, the percolation tests were started at about 10:15 AM in accordance with SJCEHD accepted ' guidelines, using clear potable water. The holes did not exhibit sloughing or caving and were 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 4 hours (SJCEHD Procedure #2), refilling as necessary to maintain the prescribed amount of water over ' the gravel. Under the observation of a representative from the SJCEHD, the last 30-minute readings of the tests were observed and the percolation rates, in minutes per inch, were calculated. Copies of our field percolation test results are attached on Figure 8. Groundwater samples were not obtained for nitrate (NO3) testing because there is no domestic ' well located within the parcel. We understand the existing facilities use water provided by the city of Stockton. The proposed new facility will also use water provided by the city of Stockton. ' The boring and percolation test holes were located in the field by visual sighting and/or pacing from existing site features; therefore, the locations shown on Figure 2 should be considered approximate. 20162869.001A/ST016R38644 Page 6 of 15 April 19, 2016 0 2016 Kleinfelder