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�77 SSS§ 3.1-3.6. The existing septic system information for the primary residence is found in Appendix G. Four repairs/additions permits to septic systems along Sedan Avenue were found in the EHD files, and are found in Appendix H. C. PERCOLATION TEST RESULTS SSS§ 6.2. To assess the permeability of the effluent receiving soils, a perc test depth of 38" was drilled in the location of the proposed primary filter bed as depicted on the Site Plans. A previous perc test was conducted on the property in February of this year, but was not conducted properly in in my opinion. Consequently, I conducted a four-hour test which should have been initially performed. SSS§ 6.3. After drilling, the sidewall of the boring was scored with a pry-bar to open potentially smeared soil surfaces. Two inches of pea gravel was placed at the bottom and a three-inch perforated PVC pipe was inserted in the test boring. After these procedures, the boring was pre- saturated with 12 inches of water approximately 24 hrs prior to the start of testing. SSS§ 6.4, 6.5. On May 1, 2020, percolation testing commenced at 0730 hrs. No standing water was observed 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 perc rate of 9.6 min/in, which was to be expected given the sandy soil type at test depth. Under Section/Table 1.10.2 of the SJC OWTS Standards, since the perc rate is between 5 MPI and 30 MPI,the minimum soil depth from the bottom of the dispersal system to groundwater must be 8 ft. No groundwater was observed in the 12 ft backhoe test pit. The filter bed is proposed to be approximately 3 ft deep, thus sufficient separation distance. 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 PERCOLATION TEST RESULTS WITH CORRESPONDING SOIL TYPE, PERCOLATION RATE AND APPLICATION RATE IN GALLONS/FV/ DAY 38 INCH DEEP PERC TEST BORING 9.6 min/inch / 0.800 gallons/ft'/day LOAMY SAND 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 Fall 2015 Lines of Equal Depth Maps and the Spring 2016 Lines of Equal Elevation Maps indicate groundwater depth and directional flow. Depth to groundwater is approximately 20 ft below grade and the groundwater directional flow appears to be in a northwesterly direction. Page -4- Chesney Consulting