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SSSPof On November 1, 2011,the perc test borings were drilled in the referenced location. The i idf the boring were scored with a pry-bar to open potentially smeared sidewalls. Two nchene gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in the borings. The test borings were subsequently pre-saturated with 12 inches of water at 0900 hrs, 24 hrs before the start of testing. SSi6. On November 2, 2011, percolation testing commenced. No standing water was obd r the 24-hr soak period in either test boring. Consequently, EHD Perc Test Procedure #2 was conducted in which testing was done over a -hour period to induce maximum soil �. saturation. The test results indicate a pert rate t 8.6 utes per inch(min/in) for the EHD Official Perc test and 13.2 min/in for the 48-inch depth est depth A summary of the pert test results with corresponding application rates in gallons of effluent accepted per square foot of soil,per day are found in Table 3: TABLE 3 PERCOLATION TEST RESULTS FOR THE DISPOSAL AREA WITH CORRESPONDING APPLICATION RATES IN GALLONS/FT2/DAY 36 INCH DEEP PERC TEST BORING C)8min/inch / 0.857 gallons/ft/day PERCOLATION RATE/APPLICATION RATE 48 INCH DEEP PERC TEST BORING 13.2 m' inch / 0.757 gallons/ft/day PERCOLATION RATE/APPLICATION RATE Awhcahm Rate adapted from California State Water Resources Control Board Cuu*lrnes for the ig r of Sewage Systems and is based on die Perc Rate. D. GROUNDWATER INFORMATION NLS§ . , SSS . . Groundwater depths and elevations throughout San Joaquin County are maps published by the County Flood Control and Water Conservation District. The most recent Lines of Equal Depth map(Spring 2011) indicates the groundwater depth to be 55 feet. This corresponds with actual water table depth determination by boring for the aforementioned St. Bernard's project. The 2003 Lines of Equal Elevation Map illustrates the groundwater directional flow to be generally in a northwesterly 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, and surrounding irrigation. SS 2. 4.2. Zte'nsely e the property has been intensely farmed, and since surrounding properties hav ee farmed for several decades,the probability for nitrate contamination in the underlying soil and groundwater is significant. A potential rise in the water table elevation may be attributed to the cropland surrounding the property to the south, east and west. NLS 2.2 .1, S 4. It is my understanding the projec will ve an on-site water well for dom c o own at this time if the well wi classified as a public well. Water chemistry should be done on a test well before conversion the_peermanent well particular for nitrate concentrations. 4 Chesney Consulting