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F o southern borings referenced above were hand-drilled,the borings were perc tested rs to ensure maximum soil saturation before the official perc test on August 27. This ure of completing a full four hour perc test was also done prior to the official perc orth half of the disposal area on September 7 and September 8. Percolation test results reveal that the perc rate at a depth of 36 inches slows by a factor of 2 in comparison to the test results at the 42-inch depth. The 36-inch depth is at the change between the dense, calcareous clay layer and the yellowish brown fine silty sand layer. The two deeper tests of 8.5 ft and 6 ft exhibit comparable test results. The following Tables summarize the results for the two sets of percolation tests conducted in the proposed disposal area: TABLE 1 PERCOLATION TEST RESULTS - AUGUST 27 42 INCH DEEP TEST BORING 102.5 INCH(8.5 FT) DEEP TEST BORING PERCOLATION RATE PERCOLATION RATE 21.4 min/inch 13.0 min/inch TABLE 2 PERCOLATION TEST RESULTS - SEPTEMBER 8 36 INCH DEEP TEST BORING 72 INCH(6 FT)DEEP TEST BORING PERCOLATION RATE PERCOLATION RATE 42.9 min/inch 17.5 min/inch Double Ring Infiltrometer Tests In addition to the conventional percolation tests described above, two double ring infiltrometer tests were conducted on the soil in the proposed disposal area. The double ring apparatus used for this test is illustrated in a photograph found in Appendix D and was done under ASTM Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometers-D3385. The infiltrometer test measures the incremental infiltration velocity, which is the quantity of flow per unit area, over an increment of time(cm3 _cm'/see). Infiltration is the downward entry of liquid into the soil and is measured by the infiltrometer. This test method involves driving two open cylinders, one inside the other, into the soil and then filling the rings with water; for these tests to a depth of 12 inches. The purpose of the outer ring is to promote one-dimensional, vertical flow beneath the inner ring. The volume of water added to the inner ring to maintain the liquid level constant with the starting value, is the measure of water that infiltrates the soil. Water volume infiltrated during 30 minute intervals for four hours is converted to an incremental infiltration velocity expressed in centimeters per hour(cm/hr), cm/sec and min/in. The infiltration tests were done at the soil surface and at 24 inches below the ground surface after pre-saturation. The surface test was done below the disked clod material in the south half of the proposed disposal area. Page-6- Chesney Consulting