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e sewage effluent management over long periods of time. This is primarily attributed to the tight, gravelly, silty soils at the leachline depth. 131 SOIL PROFILE AND PERCOLATION TESTING One deep percolation test was conducted on Parcel 1 according to San Joaquin County Department of Environmental Health regulations. No perc test was performed on the Designated Remainder per Department regulations. The perc test location is illustrated on the attached Parcel Map. Percolation test results can be found on the Field Test Data Sheet in the Appendix. Perc test results indicate a comparatively fast percolation rate of 4.2 min/in after the four hour test period. A shallow test was not conducted because the gravelly, silty nature of the shallow soils - would not have been conducive for percolation. Soil structures at the test depth consist of a silty gravely fine sand (GM/SG). No hardpan layer was encountered during the drilling procedure. The boring was pre-saturated 50% of the total depth, 24 hrs prior to starting the perc test to -- induce saturated soil conditions. 141 LOCAL GROUNDWATER AND SURFACE WATER INFORMATION The static water table depth, or the zone of saturation is located at approximately 62 feet below grade from the sounding of a well in the northeast corner of Parcel 1. The 1996 "Lines of Equal Depth" published by the San Joaquin County Flood Control District does not reference the static water table _ depths in this area. It is possible there may be perched water table conditions under the subject property at a higher elevation than the static water level and this should be investigated if seepage pits are ever installed. There is no potential for septic impact to any surface waters, providing applicable distance requirements are followed. The property is not in the flood plain. The water sample obtained for analysis was drawn from the above-referenced well. The nitrate _. concentration in this well water was<1 ppm NO3. The Maximum Contaminant Level (MCL) for NO3 in drinking water is 45 ppm. The pesticides DBCP and EDB were not detected (ND). A nitrate concentration of<1 ppm indicates the well is probably comparatively deep, pumping water from underlying aquifers which have not been impacted from nitrogen contributors, such as agricultural operations, septic systems or rainfall. No well logs were available in the area to verify if clay layers may have helped attenuate the downward migration of nitrate molecules. Groundwater directional flow is unknown but probably towards the southeast. 2