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PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability of the effluent receiving soils, two perc test depths of 36" and 96" were drilled with a B-24 Mobile Drill Rig in the location of the proposed primary filter bed as depicted on the APN Map. SSS§ 6.3. After drilling, the sidewall of the shallow boring was scored with a pry-bar to open potentially smeared soil surfaces. Two inches of pea gravel was placed at the bottom of both borings and a three-inch perforated PVC pipe was inserted in each test boring. After these procedures, the borings were pre-saturated with 12 inches of water approximately 24 hrs prior to the start of testing. SSS§ 6.4, 6.5. On November 26, 2019, percolation testing commenced at 0730 hrs. No standing water was observed in either boring after the 24-hr soak period. Consequently, EHD Perc Test Procedure #2 was conducted. Testing was done over a four-hour period to induce maximum soil saturation. The test results indicate a relatively rapid perc rate of 13.9 min/in for the shallow boring and 7.8 min/in for the deeper test boring. A summary of the perc test results with corresponding application rates in gallons of effluent accepted per square foot of soil per day are illustrated below in Table 2: TABLE 2 A PERCOLATION TEST RESULTS WITH CORRESPONDING SOIL TYPE, PERCOLATION RATE AND APPLICATION RATE IN GALLONS / FT2 / DAY 36 INCH DEEP PERC TEST BORING 13.9 min/inch / 0.743 gallons/fe/day 96 INCH DEEP PERC TEST BORING 7.8 min/inch / 0.800 gallons/f 2 /day 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 Fall 2015 and 2016 Lines of Equal Depth Maps and the Lines of Equal Elevation Maps indicate groundwater depth and directional flow. Depth to groundwater is approximately 35-40 ft below grade and the groundwater directional flow appears to be in a northeasterly direction. NLS§ 2.2,3.1, SSS§ 4.2. Surrounding agricultural properties are currently farmed and have been for decades, and surrounding properties have been on septic systems so the potential for nitrate contamination of the underlying groundwater can be considered significant. NLS§ 2.3, SSS§ 4.3, 4.4, 4.5. There is no well on, nor is a well proposed to be drilled the property. A water sample was obtained from the city water line that will ultimately serve the property. Test results show a nitrate-nitrogen concentration of 0.2 ppm. Page -3- Chesney Consulting