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rFAIIerc test borings were drilled on March 29, 2004. Since the test borings contained high gravel nt, there was no need to score the inner soil surfaces. Three-inch O.D. perforated pipe was placed in each five-inch diameter boring after two inches of pea gravel was added. On the morning of April 4, the two test borings on Parcel 1 were presaturated with 12 inches of clear water. Perc testing commenced the following day, April 5 at 10:00 A.M. There was no standing water in the two test borings after the 24-hour pre-saturation period. Each boring was perc tested for four hours in compliance with S.J.C. Policy EHD 02-02. During the perc testing of Parcel 1, the perc test borings for Parcels 2 and 3 were presaturated for testing that began the morning of April 6, as witnessed by EHD staff. There was no standing water in any of the three test borings at the start of testing at 10:00 A.M. April 6. The perc tests for Parcels 2 and 3 were also conducted for four hours. As illustrated on the FIELD PERCOLATION TESTING REPORTS found in Appendix 4, each of the shallow perc test borings on each of the three Parcels exhibited acceptable perc rates that can be considered moderately rapid. The deeper perc test done on Parcel I indicated failing rates and the deeper perc test for Parcel 2 indicated a relatively slow perc rate. The perc test results are summarized below for each of the three Parcels: qg ;. PERCOLATION' TEST RESULTS PARCEL PARCEL 1 PARCEL 2 PARCEL 3 PERC DEPTH PERC RATE PERC RATE PERC RATE SHALLOW 18.8 min/in @ 36 Inch Depth 20.8 min/in @ 36 Inch Depth 12.2 min/in @ 42 Inch Depth FERC DEPTH INTERMEDIATE FAILED @ 110 Inch Depth 41.7 nun/in @ 56 Inch Depth No Pere Test Conducted at the PERC DEPTH Intermediate Depth Due to Auger Refusal III. NITRATE LOADING STUDY RESULTS A. GROUNDWATER INFORMATION The static water level under the center of the project is located approximately 172 feet below grade according to the Well Drillers Report referenced above. Depth to first water, which can be considered the water table, was encountered at 150 feet. The 1999 Lines of Equal Depth and Lines of Equal Elevation Maps published by the San. Joaquin County Flood Control District do not illustrate groundwater depths and elevations in this region due to extreme variability. Therefore, groundwater gradient and velocity cannot be calculated without sophisticated monitoring and testing. 6 Chesney Consulting