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• 1989 Production and Geologic Conditions <br /> Cyprus Orchard Valley Coal Corporation (COVCC) produced <br /> approximately 517, 156 tons of coal from the Orchard Valley West <br /> Mine in 1989 from Federal Coal Lease #C-37210. The 1989 production <br /> was for an eleven month period as were 1988 and 1987. Market <br /> conditions in conjunction with shaft development limited the <br /> production in January. Again, market conditions necessitated <br /> halting production in December with operations at full production <br /> levels for the remainder of the year. <br /> Mining at the orchard Valley West Mine during 1989 consisted of <br /> both pillar retreat extraction and advance Mining. Panel G partial <br /> pillar extraction continued through the 1st and 2nd Quarters. <br /> Panel H advance was started in the 3rd quarter and continued <br /> through the end of the year. Geologic and mining conditions were <br /> similar between the two panels. The major difference was found in <br /> the coal parting which tended to be thicker and of higher ash <br /> content as mining progressed north and west. A more concise <br /> description of the conditions encountered in each section is <br /> summarized as follows: <br /> Panel G• <br /> • Mined Length: 3900 ft. of advancement and pillar extraction. <br /> Overburden thickness: 400 - 950 ft. <br /> Mining height: 9-11 ft. <br /> Roof: Comprised of mudstones with a high concentration of <br /> pots and slickensides through 28 X-cut. A sandstone channel was <br /> encountered approximately 10 feet above the coal seam throughout <br /> the remainder of the section. Top coal of 4-5 feet in thickness <br /> was left to prevent roof problems that would normally be <br /> encountered with this strata type. <br /> Ribs: Moderate to heavy rib sloughage occurred in local <br /> areas. 4 ft. and 5 ft. rib bolts were installed in areas of we$k <br /> cleated coal and high mining heights. <br /> Floor: The lower "D" coal seam was used as floor which <br /> provided competent conditions. <br /> Anomalous conditions: Shear zones were prevalent in the areas <br /> from #20 to # 25 X-cut. Small seeps from the roof were <br /> encountered. The interburden thickened as the panel was driven <br /> north with the interburden contributing to a high ash content which <br /> halted mining at #34 crosscut. Attempts were made to mine the <br /> lower "D" using interburden as roof material with limited results. <br /> • <br />