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rall ides were scarified to open smeared soil surfaces that may have formed due to the clay soil tructure. The test borings were then pre-saturated with six inches of clear water. After 24 hrs, the water had seeped away. Percolation testing commenced on July 30, 2002 under .S.E.P.A. and San Joaquin County Environmental Health guidelines. As illustrated on the attached FIELD PERCOLATION TESTING REPORT, perc rates for the test boring shows favorable percolation considering the clay soil. The perc rate is approximately twice as fast as the perc test done on parcel 255-25-09. Since the perc test was done in the alfalfa field, this relatively fast perc rate may be attributable to soil cracking,root casts, earthworm casts and the slightly siltier soil at the 42-inch depth. By conducting a perc test in the subject parcel, the Soil Suitability Study requirements for this parcel are fulfilled. For convenience, the percolation test conducted on parcel 255-25-09 for the original Soil Suitability Study is illustrated below, along with the percolation done for this Study. PERCOLATION TEST RESULTS PARCEL No 42 INCH PERC RATE IN DATE PERC TEST MINUTES/INCH CONDUCTED 255-25-09 25.0 MINAN February 22,2002 255-26-13 13.6 MIN/IN July 30,2002 D. GROUNDWATER INFORMATION Groundwater depths and elevations are illustrated on maps published by the San Joaquin County Flood Control and Water Conservation District. However, due to the variability in groundwater depths and elevations for this region, they are not denoted on the lines of equal depth or equal elevation. Consequently, depths to groundwater were measured by two methods. As referenced above, the first method was by a backhoe test pit, which was excavated at the north-center of APN 255-26-13. Phreatic water (zone of saturation)was encountered at 12 feet below. The second method of static groundwater depth determination, was Ie measurement of the standing water level (SWL) in an irrigation well on the subject parcel, that does not have a pump and is no longer used. This well is approximately 100 feet away from the backhoe test pit and is denoted on the site plan. The SWL was measured in this well at 88 feet below grade, with a well depth of more than 150 feet. A Well Log was not found at the Environmental Health Department for this well, any other subject property well, or any surrounding property well. Explanations for this difference in groundwater depths may be attributable to: 1.) The irrigation well is an "open-bottom" well and is only measuring the hydraulic pressure of the aquifer where it is open to, 2.) The well may have collapsed, and again, is only measuring a particular aquifer pressure, and 3.) There is a thick, clay aquitard between the highest aquifers and the deeper aquifers. 5 Chesney Corrsufting