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kTJ KLEINFELDER Procedure #2). As specified, the last two 30-minute readings were recorded under the observation of a representative from the SJCEHD and were used to calculate the percolation rate in minutes per inch. The estimated percolation rates are summarized below. A copy of our field percolation test results signed by a representative. from SJCEHD is attached. Details of each test can be found on the percolation test sheet. During the percolation tests, groundwater rose in the deeper percolation test holes at locations P-2 and P-3. Therefore, the percolation tests in these holes could not be run. As stated in Section 3, published reports indicate that groundwater is at a depth of about 105 to 130 feet below the existing site grade in the project area. It is our opinion that the rising water was a perched groundwater condition likely caused by local irrigation. Test Number Performed Depth (feet) Percolation Rate (min./inch) 3.0 Did not percolate P-1 9.0 83.3 3.2 25.0 P 2 8.0 Water elevation increasing in hole ' P-3 3.0 125.0 11.0 Water elevation increasing in hole On August 2, 2004, the same drill rig returned to the site and reinstalled two deep percolation tests at the locations of the P-1 and P-3. The holes were drilled and prepared before noon in accordance with SJCEHD criteria, as described above. The percolation tests were started at about 9:00 AM under sunny and warm weather on August 3, 2004, in accordance with accepted guidelines using clear potable water. The approximate depth of each test hole below existing site grade is shown on the following table. The holes did not exhibit sloughing or caving. At the time of testing no standing water from the presoaking remained in either test hole. A copy of our field percolation test results signed by a representative from SJCEHD is attached. Details of each test can be found on the percolation test sheet. Test Number Performed Depth (feet) Percolation Rate (min./inch) P-1 8.0 Did not percolate P-3 12.3 20.8 / 7. CONCLUSIONS The results of percolation test P-2 in proposed Parcel 2 indicates that the near surface soils (at a depth of about 3.2 feet) exhibit suitable percolation characteristics at the location tested. A suitable soil condition for a test at this depth is defined as a stratum capable of percolating water at a rate of 60 min/inch or faster. Based on this result, a conventional septic tank/leach trench sewage disposal system designed per SJCEHD criteria should adequately serve the proposed residence. 42270.G01/ST041383 October 15,2004 ©2004 Kleinfelder, Inc. Page 4 of 6