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if' <br /> No standing w22222�ater was observed in the other three test borings, therefore EHD Perc Test Procedure <br /> i <br /> #2 was conducted. Testing was done over a four-hour period to induce maximum soil saturation. , . <br /> Only the 42-inch test boring and the 280 inch deep boring are recognized as`official'by EHD. <br /> The test results indicate virtually nonexistent perc rates at the 42 inch depth test depth, and favorable <br /> perc rates at the deeper depths. A summary of the perc test results with corresponding application <br /> rates in gallons of effluent accepted per square foot of soil per day are illustrated in Table 2: <br /> TABLE 2 <br /> PERCOLATION TEST RESULTS WITH CORRESPONDING <br /> APPLICATION RATES IN GALLONS /Fr=/DAY <br /> 42 INCH DEEP PERC TEST BORING 0 min/inch / 0 gallons/ft/day <br /> PERCOLATION RATE/APPLICATION RATE <br /> (OFFICIAL PERC TEST) <br /> 88 INCH DEEP(7.3 FT)PERC TEST BORING 6.8 min/inch / 0.970 gallons/ft/day <br /> PERCOLATION RATE/APPLICATION RATE <br /> (UNOFFICIAL PERC TEST) <br /> 140 INCH DEEP(11.7 FT)PERC TEST BORING 11.4 min/inch / 0.779 gallons/ft/day <br /> PERCOLATION RATE/APPLICATION RATE <br /> (UNOFFICIAL PERC TEST) <br /> 280 INCH DEEP(23.3 FT)PERC TEST BORING 10.0 min/inch / 0.800 gallons/ft/day <br /> PERCOLATION RATE/APPLICATION RATE <br /> (OFFICIAL PERC TEST) <br /> Application Rale adapted from California Stare Water Resources Control Board Guidelines for the Design ofSeaage Systems and is based on We Pac Raft. <br /> D. GROUNDWATER INFORMATION <br /> NLS§ 2.1, SSS§ 4.1. Groundwater depths and elevations throughout San Joaquin County are <br /> illustrated on maps published by the County Flood Control and Water Conservation District. The <br /> 1999 Lines of Equal Depth Map indicate the groundwater depth to be approximately 60 feet below <br /> grade. The 2003 Lines of Equal Elevation Map illustrates the groundwater directional flow to be in <br /> a southeasterly direction. <br /> Well logs were found in EHD microfiche files for two nearby wells that illustrate well construction <br /> details and underlying lithology. Subsurface lithology indicate intervening strata of sand and clay. <br /> NLS§ 2.2,3.1, SSS§ 2.1, 4.2. Since the subject property and surrounding properties have been (_Z I ) <br /> -29 intensely farmed for several decades, the potential for nitrate contamination to the upper <br /> groundwater aquifers is significant. It is recommended that a test well be drilled to test the aquifers <br /> r j at the anticipated well completion depth for the wells that will serve any future project. <br /> NLS§ 2.3, SSS§ 4.3,4.4, 4.5. 4.6. As referenced, the on-site ag irrigation well could not be <br /> 2,3 sampled since the pump could not be repaired, and there was no water in the well. It is my <br /> understanding this well is approximately 80 ft deep, which places it deeper than the apparent <br /> groundwater depth at 60 feet. <br /> 5 <br /> Chesney Consulting <br />