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Test Boring No. 3 was further from the entry and encountered <br />the "E" seam at a depth on the order of 78.5 feet below the ground <br />surface. At this location, the ",Fz'' seam was intact and unburned. <br />It was found to have a thickness on the order of 10.3 feet. The <br />floor and roof rock were found to be relatively compact and unaltered. <br />Rock observed in the floor of the proposed mine at this location con- <br />sisted of a shale underlain by interbedded siltstone and sandstone. <br />The mine roof consists of an interbedded series of shales, siltstones <br />and sandstones. Typical thickness of the shale units are on the <br />order of one foot while siltstone units were on the order of 2.5 to <br />3 feet. Sandstone units were typically 3 to 3.5 feet in thickness. <br />ANALYSIS OF DATA: <br />As mentioned previously, physical property testing was performed <br />on samples of the NX core obtained from these test borings. On the <br />coal seam itself, the unconfined compressive strength was obtained <br />for subsequent use in pillar design. In the roof roc}: materials, <br />several different types of tests were obtained. The modulus of rup- <br />ture of the roof materials were obtained in order to permit modeling <br />of roof performance in bending using beam theory. In addition, the <br />unconfined compressive strength along with a determination of Young's <br />modulus and Poisson's ratio were obtained in order to analyze de- <br />flections in the application of beam theory and as important para- <br />meters which will be used in the future treatment of the problem using <br />more modern techniques. Testing procedures also produced information <br />on in-place density. <br />2 <br />