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1990 Production and Geologic Conditions <br />• Cyprus Orchard Valley Coal Corporation (~VCC) produced approximately 584,810 <br />tons of coal fresn the Orchard Valley west mine in 1990 under Federal Coal Lease <br />'-)C-37210. Due to slightly improved market conditions, prvciuction was :vstained <br />throughout the twelve months comprising calendar year 1990 in contra=;t to the <br />eleven production months experienced during each of the previous three years. <br />Mining at the Orchard Valley West mine during 1990 entailed both pane]. advance <br />development and pillar retreat extraction. Panel H advance mining continued and <br />was cortipleted in March. Subsequent pillar retreat mining of Parxal H was <br />cort~leted in September. Development of the II West Submains continued to the <br />west and was followed by the initial advance development of Panels A and A+ to <br />ca~lete the year. <br />Panel H: <br />Mined Length: 600 feet of panel advance development and approximately 6000 feet <br />of pillar retreat extraction. <br />Overburden 4hicknass: Variable from 600 feet at southern end of panel to 1100 <br />feet at northern erd. <br />Mining Heic~t: 6-16 feet. <br />• Roof: Comprised of mudstones with a high concentration of pots and slickensides <br />throughout the section. At crosscut 25, mining praceeder] in the lower portion <br />of the seam below the contact of the split rock and the bottom of the upper "D" <br />seam. Otherwise, 2-3 feet of top coal was left to prevent roof probl~sns that <br />would result from air slate . <br />Ribs: Moderate to heavy rib sloughage occurred on local areas. Rib bolts were <br />installed on the walkway side of the belt for safety of employees travelling the <br />beltway. Additional bolts were installed on areas of high mining heights and on <br />corners where slabbing ribs would cause a hazard to employees. <br />Floor: 'IY~e lower "D" seam was used as floor thrax~out the section. Where <br />mining was in the loser "D" seam exclusively, the floor coal was thin and at <br />times a fire-clay material was encountered. <br />Anomalous Corditions: Shear zones were prevalent in the section from crosscut <br />22 to the extent of mining in 1989. Rock spars crisscrossed the panel from <br />approximately crosscut 9. EWidence of minor post-depositional faulting <br />perpendicular to the areas major fault system were encountered. As. mining <br />proceeded north and west the thickness of the interburden increased causing the <br />ash to increase. To maintain the quality of the salable prochict, large <br />quantities of waste material were shipped to the West Ridge waste Pile. <br />II West Submains <br />• Mined Length: 1300 feet of submain advance development. <br />1 <br />