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✓SSS§ 6.3. On October 31, 2007, drilling commenced. The sidewalls of the shallow boring was scored with a pry-bar. This is a critical procedure and"opens"potentially smeared surfaces. The deeper nine foot boring could not be scored due to its depth. 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 November 1, 2007,percolation testing commenced. Four inches of standing water was observed after the 24-hr soak period in the shallow boring. Consequently, EHD Perc Test Procedure#1 was conducted. No standing water remained in the deep boring, so Perc Test Procedure#2 was conducted. Testing was done over four hours to induce maximum soil saturation. The test results indicate a very slow (failed)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 in Table 2 below for the proposed disposal area: TABLE 2 PERCOLATION TEST RESULTS AND RELATED DATA SHALLOW PERC TEST POST SOAK PERC TEST RESULTS APPLICATION RATE IN DEEP PERC TEST PERIOD GALLONS/FV/DAY STAT 1 4 Inches 125.0 min/in 0.200 gals/sq ft/day 36 INCHES Standing Water in Hole : - - 108 INCHES No Standing 6.6 min/in 0.971 gals/sq ft/day (9 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 (1999) indicates the groundwater depth to be approximately 10 feet. However, the new on-site domestic well was sounded on September 27, 2007 and found to have a standing water level depth of 23.8 feet at the top of casing. The casing is approximately one foot above surrounding grade, which makes the depth to the water table theoretically 22.8 feet. The 2003 Lines of Equal Elevation Map illustrates the groundwater directional flow to be generally in a westerly direction, toward the Delta. The well log for the new domestic well for the subject property illustrates 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 Chesney Consulting