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At the time of our field investigation the conveyor was not in operation. However, during our <br />I previous density testing the refuse material was very wet as it came off the conveyor, and was roughly <br />1 <br />6096 shale and 4096 coal. Our observations indicated the refuse is generally minus 6 inch gradation, <br />and appears to have about 50% passing the No. 4 sieve. Most of the material is minus 3-inch in size. <br />FIELD INVEST1taA11ON <br />Density Testing <br />~ Our previous density investigation as well as part of this investigation were performed using <br />[7 <br />a down-hole nuclear density gauge (CPN Model Number 501 DR). This instrument allows us to test <br />density of in-situ materials. For this test an exploratory boring is first drilled. Athin-walled steel casing <br />is then installed into the hole to prevent the soil from caving and being disturbed. The outside of the <br />casing has the same nominal diameter as the drill hole to create a tight "fit" for the casing. Drilling <br />disturbance can create voids around the casing. The probe from the gauge is lowered into the hole <br />• <br />to predetermined depths. For this investigation, we measured the density at one-foot increments from <br />the surtace to depths of 12 feet at 2 boring locations. A test was taken at each location and wet <br />~ density, dry density and moisture content were recorded in pounds per cubic foot. <br />Because of the high coal content of the refuse and principles upon which the nuclear gauge <br />operate, moisture readings from the down-hole device are much higher than actual moisture conditions <br />~ in the fill. To provide a means for correcting moisture we performed down-hole nuclear tests as <br />described above, along with excavating a pit alongside each casing to obtain moisture correlation <br />samples and to take additional density tests with a standard nuclear type device (froxler Model <br />~ Number 3411-b) and large sand cones. With this additional information we "corrected" the moisture <br />• <br />and density readings from the down-hole nuclear device from the previous study. We found the sand <br />cone tests were not representative because the wet materials "squeezed" into the test hole. Thus, <br />2 <br />• <br />