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I y 7Afterborings were drilled, the sidewalls were scored with a pry-bar and the loose material Two inches of fine gravel was placed at the bottom and three-inch perforated PVC pipe ed in the test boring. The two perc test borings were pre-saturated on February 13, 2006 at 1000 hrs with 12 inches of water. In addition to the percolation test borings, a Double Ring Infiltrometer soil test was also conducted. This test measures one-dimensional water infiltration at the assumed soil/effluent interface. The test area was excavated and the test rings were set at approximately 24 inches below grade, as illustrated in the photographs. This test depth was set again, on the premise that a filter bed was eventually required to be installed due to groundwater and/or soil conditions. (§ 6.4) On February 14, 2006, 1000 hrs,percolation testing commenced. There was no standing water after the 24-hour soak period in the 42 inch boring; therefore, EHD Perc Test Procedure#2 was conducted for this test boring. Approximately 3 inches of water was in the 24-inch deep shallow boring, as illustrated in Table 1 below. Consequently, EHD Perc Test Procedure#1 was conducted for this test. Due to difficulty in finding the test location and communication failures, the last half hour of the four-hour test was not witnessed by Mike Escotto,R.E.H.S. of the Sart Joaquin County Environmental Health Department. However, after the testing was completed,both Mr. Escotto and Mike Huggins, EHD Supervisor were on-site to observe and verify the percolation test borings, the double ring infiltrometer test, and the depth to the water table in the backhoe test pit. Perc test results reveal a rate of 6.8 minutes/inch(min/in) for the 42-inch deep boring and a failing rate of 125 min/inch for the shallow 24-inch boring. The maximum acceptable perc rate is 60 min/in for shallow perc tests. (§ 5.4 and 6.8) Table 1 below illustrates the Parcel APN number, septic system structure based on the depth of the passing perc rate, soil characteristics, post soak period status and perc test results for the respective perc test depth: TABLE 1 PERCOLATION:TEST.RESULTS 'KITH RELATED DATA PARCEL AND SEPTIC PERC TEST DEPTH POST SOAK PERC TEST RESULTS SYSTEM STRUCTURE SOIL TYPE I STATUS PERIOD APPLICATION RATE Parcel 129-040-40 24 Inch Test Boring Approx. 3 Inches FAIL 125 min/in Leachlines Trenches Compacted fine sandy loam Standing Water 0.200 gals/sq ft/day Not to Exceed 30 Inches in Dept 42 Inch Test Boring No Standing 6.8 min/in Loamy sand Water in Hole 0.971 gals/sq ft/day INFIL'TRATI4NTE ry r ST RESULTS INFILTRATION RATE IN MINUTES/INCH AND APPLICATION RATE 107 min/in 0,200iallons/ftZ/da 4 g Y Page -4- Chesney Consulting