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t [3] PROPOSED DEVELOPMENT OF THE SUBJECT SITE It is proposed to split two acres off of 19.69 acres to form two parcels, Parcel No. 2 being±2.0 acres and Parcel l consisting off17.69 acres. As referenced earlier, it is proposed to place a mobile home 4., on Parcel 2, [41 SOIL PROFILE AND PERCOLATION TESTING An exploratory boring performed in the center of the subject property indicates a slightly varied w. soil structure throughout the soil profile. The predominate soil type from grade to 10 ft is a silty, ' very fine sand. The silt content of the soil increases slightly with depth, to a medium silty sand at boring termination. A hardpan layer was not encountered but does exists in the regional location of the subject property at variable depths. ON. During the drilling process for the shallow(48") percolation test holes, the soil structure was carefully analyzed, This depth represents the maximum depth of a leachline trench where effluent percolation F or "wetting front" will occur in native soil. Therefore, pert tests were performed at this depth. Our percolation tests were conducted according to San Joaquin County Department of Environmental Health regulations. The Field Test Data Sheets with the percolation test results can be found in the Appendix. The 42 inch soil profile for both parcels has a relatively high sand content, as evidenced by the fast percolation rates at this depth. Due to these favorable pert rates at the shallow depth, deep pert tests were not performed. A discussion of these rates, and septic system design recommendations will follow in the Conclusions section of this report. [5] LOCAL GROUNDWATER AND SURFACE WATER INFORMATION The groundwater, or the zone of saturation is located at approximately 18 ft below grade 60 according to maps published by the Flood Control District. There was no evidence of a perched water table condition during our exploratory boring procedures and there is no potential impact to surface waters in the area. LM ` Analysis of water drawn from a domestic well adjacent to the south of the existing residence on Parcel 1, illustrates a high concentration of nitrate at 62 ppm NO3; The pesticide DBCP was detected in a concentration of 6.7 pg/L which is well over the Maximum Contaminant Level (MCL) of 0.2 Mg/L, This pesticide must have been used in the surrounding vineyards before they were canceled and banned by the EPA. L. 53. �u<�iity Control �nspect¢on i g