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FFbefore On November 29, 2007, the perc test boring was hand-drilled in the referenced location. ls of the boring was scored with a pry-bar to open potentially smeared sidewalls. Two e gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in The test boring was subsequently pre-saturated with 12 inches of water 1000 hrs, 24 hrs tart of testing. SSS§6.4, 6.5. On November 30, 2007,percolation testing commenced. No standing water was observed after the 24-hr soak period. Consequently, EHD Perc Test Procedure#2 was conducted in which testing was done over a four-hour period to induce maximum soil saturation. The test results indicate a perc rate at 8.9 minutes per inch (min/in). A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil, per day are found in Table 2: TABLE 2 PERCOLATION TEST RESULTS FOR THE DISPOSAL AREA WITH CORRESPONDING APPLICATION RATES IN GALLONS/FTz/DAY 40 INCH DEEP PERC TEST BORING 8.9 min/inch / 0.857 gallons/ft/day PERCOLATION RATE/APPLICATION RATE Application Rate adapted from California State Water Resources Control Board Guidelines for the Design of Sewage Systems and is based on the Per:Rate. D. GROUNDWATER INFORMATION NLS§ 2.1, SSS§4.1. Groundwater depths and elevations throughout San Joaquin County are illustrated on maps published by the County Flood Control and Water Conservation District. The most recent Lines of Equal Depth map (1999) indicates the groundwater depthto be 10 feet. The 2003 Lines of Equal Elevation Map illustrates the groundwater directional'flow nerally in a westerly direction toward the San Joaquin River. Groundwater flow in this locale is extremely variable due to several influences such as the time of the year, depth of the San Joaquin River, and tidal action. From groundwater studies that occurred directly north of the property,the groundwater gradient was determined to be in a northeasterly(N 33° E) direction in 2002. This groundwater flow direction was obtained from monitoring wells. A well log for a domestic well on the property south of the subject property illustrates varied geological strata of clay and sand down to a depth of 145 feet,with a clay layer from 17 to 30 feet. A well log for the on-site Monitoring Well also illustrates a clay layer existing from 19 to 25 feet. Groundwater research in the scientific literature references that there may be significant denitrification potential within aquifers or saturated zones composed of a fine(vs. a coarse) soil fraction. SSS§ 2.1,4.2. Since the property was part of the former Hayres Chicken Ranch, and since surrounding properties have been intensely farmed for several decades, the probability for nitrate contamination in the underlying soil and groundwater is significant. This was evidenced by the soil chemical analysis for this Study and the water table analysis conducted for the Preston project. 4 Chesney Consulting