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SSS§ 6.3. On March 13, 2014, drilling commenced. The sidewalls of the two borings were S� scored with a pry-bar. This is a critical procedure and "opens"potentially smeared surfaces. Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe was inserted in each test boring. The boring was pre-saturated with 12 inches of water at 1000 hrs, 24 hrs before the start of perc testing. SSS§6.4,6.5. On March 14, 2014, percolation testing commenced. No standing water was measured in either test boring after the 24-hr soak period. Consequently, EHD Perc Test Procedure #2 was conducted. Testing was done over four hours to induce maximum soil saturation. The test results indicate a medium percolation rate for the shallow test boring, and a relatively rapid perc rate for the deep test boring. A summary of the perc test results and related data, with corresponding application rate in gallons of effluent accepted per square foot of soil, per day are found below: TABLE 2 PERCOLATION TEST RESULTS AND RELATED DATA SHALLOW PERC TEST POST SOAK PERC TEST RESULTS APPLICATION RATE IN DEEP PERC TEST PERIOD GALLONS/FT2/DAY STA I No Standing 35.7 min/in 0.52 gals/sq May 36 INCHES Water in Hole (3 Feet) 84 INCHES No Standing 8.1 min/in 0.96 gals/sq ft/day (7 Feet) Water in Hole Application Rates adapted from:California State Water Resources Control Board Guidelines for the Design of Sewage Systems. 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 (2012) indicates the groundwater depth to be approximatel feet. The on-site domestic well was sounded on March 6,2014 and found to have a standing er level depth of 28 feet from the top of casing. The casing is approximatelv one foot above surrounding grade,which makes the depth to the water table theoretical 27 fee . The static water level was measured in this well at 23 feet below grade in September of , so there has been a drop of approximately 4 feet in 6.5 years. The 2012 Lines ation Map illustrates the groundwater directional flow to be generally i westerly direc 'on, toward the Delta. The well log for the on-site domestic well for the subjec ates varied geological strata of clay, sand and gravel down to a depth of 290 feet. Groundwater research in the scientific literature suggests there may be significant denitrification potential within aquifers or saturated zones composed of a fine clay soil fraction. 4