Laserfiche WebLink
Panel H <br /> • Mined Length: 3500 ft. of advanced mining during 1989.. 250 <br /> ft. of development had occurred during the development of II West <br /> Submains in 1987. <br /> Overburden Thickness: 600 - 1100 ft. <br /> Mining Height: 6-16 ft. <br /> Roof: Comprised of mudstones with a high concentration of <br /> pots and slickensides throughout the section. At crosscut 25, <br /> mining proceeded in the lower portion of the seam below the contact <br /> of the split rock and the bottom of the upper "D" seam. Otherwise, <br /> 2-3 feet of top coal was left to prevent roof problems that would <br /> result from air slacking. <br /> Ribs: Moderate to heavy rib sloughage occurred in local <br /> areas. Rib bolts were installed on the walkway side of the belt <br /> for safety of employees traveling the beltway. Additional bolts <br /> were installed in areas of high mining heights and on corners where <br /> slabbing ribs would cause a hazard to employees. <br /> Floor: The lower "D" seam was used as floor throughout the <br /> section. Where mining was in the lower "D" seam exclusively, the <br /> floor coal was thin and at times a fire-clay material. was <br /> • encountered. <br /> Anomalous Conditions: Shear zones were prevalent in the <br /> section from crosscut 22 to the extent of mining in 1989. Rock <br /> spars criss-crossed the panel from approximately crosscut 9. <br /> Evidence of minor post-depositional faulting perpendicular to the <br /> areas major fault system were encountered. As mining proceeded <br /> north and west the thickness of the interburden increased causing <br /> the ash to increase. To maintain the quality of the salable <br /> product, large quantities of waste material were shipped to the <br /> West Ridge Waste Pile. <br /> • <br />