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Since the internal area of a 18-inch deep x 4.5 inch dia. boring is 255 int or 1.8 ft', the application rate for the surface soils is theoretically 28.2 gallons/ftZ/day. The pere test and hydraulic conductivity test results are summarized below: PERCOLATION/HYDRAULIC CONDUCTIVITY TEST RESULTS PARCEL 42 INCH PERC RATE IN 7.5 FT PERC RATE IN 18" HYDRAULIC No MIN/INCH MINANCH CONDUCTIVITY TEST M GALS/SQ FT/DAY 193-230-08 42 MIN/IN 17 MINAN 28.2 gallons/ft2/day D. GROUNDWATER INFORMATION Groundwater depths and elevations are illustrated on maps published by the San Joaquin County Flood Control and Water Conservation District. Since there are monitoring wells on APN 190- 230-07, groundwater depth, direction and gradient have been determined from these wells, which were installed in November of 2001. Over the last several years, it is highly probable that there have been fluctuations of at least t5 ft in groundwater elevation under the subject properties. The critical issue regarding the groundwater elevation is there must be sufficient distance between the bottom of a filter bed, leachline trench, or sump and the highest anticipated depth to groundwater for sufficient treatment(destruction) of bacteria and viruses to occur. This is generally accepted to be five feet. Therefore, sufficient distance currently exists between the bottom of a filter bed, leachline trench or seven feet deep sump and the static water table depth. To take advantage of the denitrification and treatment potential of the soil, a filter bed or leachfield that is high in elevation should be installed to force septic effluent to travel the greatest distance before encountering the water table. The well log for a domestic well on the Widmer property directly south of APN 190-230-08 illustrates varied geological strata of clay and sand down to a depth of 145 feet, with a clay layer from 17 to 30 feet. The well log for the on-site Monitoring Well also illustrates a clay layer existing from 19 to 25 feet. There is ongoing research at the University of Colorado which suggests there may be significant denitrification potential within aquifers or saturated zones composed of a fine (vs. a coarse) soil fraction. GROUNDWATER ANALYTICAL TEST RESULTS As illustrated in the Soil and Water Table Test Results on Page 4,two top water table samples from the East and West Test Pits were analyzed for nitrate concentrations. Test results reveal the water table to have a nitrate (as NO3) concentration of 168 ppm and 224 ppm for the West and East Test Pits, respectively. 6 Chesney Consulting