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Roof: Co~rised of mudstones tending to air slack. `Ibp opal of 2-3 feet in <br />thic7mess was left on the roof to prevent problems associated with this <br />strata type. <br />Rill: Rib sloughage was minimal with ribs standing very well. <br />Floor: The lower "D" seam was used as floor which provided omnpetent corriitions. <br />Anomalous Conditions: Small seeps from both roof and floor sources were <br />encountered throughout development of the section. <br />Panel C• <br />Mined Length: Approximately 2850 of panel advance development to crosscut <br />24. <br />Overburden Zhiclmess: Varying from approximately 300 to 900 feet. <br />Mining Height: 9-11 feet on advance. 18 feet maximum on retreat in partial <br />extraction areas. <br />Roof: Comprised of muddtones tending to air slack. `Ibp coal of 2-3 feet in <br />thicJmess was left on the roof to prevent problems associated with this <br />strata type. <br />Ribs: Rib sloughage was minimal with rill standing very well. <br />• Floor: 'Ifie lower "D" seam was used as floor which provided cortg~etent conditions. <br />Anomalous Conditions: Small seeps from both roof and floor sources were <br />encountered throughout development of the section. <br />II West SUlmains: <br />Mined Length: 3800 feet of submain advance development west of South III <br />SUlanains. <br />Mining Height: 8.5-9.5 feet. SUk~nains developed in upper "D" seam only. <br />Roof: Comprised of maddtones arxi sandstones with a high concentration of pots <br />and slickensides. Roof coal was not left in place. Development was <br />meshed on roof through entire section to ensure roof stability. <br />Ribs: Rib sloughage was minimal with ribs standing well. <br />Floor: Interburden between upper and lower "D" seams was used as floor and <br />provided competent conditions. <br />Anomalous Conditions: Upper "D" opal seam tended to thin with westwan3 <br />development and thicken again by approximately crosscut <br />30; roof instability required steel mesh installation <br />throughout development. Several significant roof falls <br />• encountered. 'Typical seeps from both roof and floor. <br />blibeidence Impacts 1991 <br />2 <br />