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This relationship between load and strength is the worst case and will <br />occur only in rooms where pillar strength is less critical due to the room pillars <br />being shorter lived than those in mains and submains. Most of the property is less <br />than 1000 feet deep and the safety relationship, of course, improves beyond the <br />example calculation. <br />The mining plan for each of the three pane la (1st - 3rd North) will be to <br />firsC drive the entries to the northern boundary defined on Exhibit C. Then rooms <br />will be developed on similar projections. The last block developed by each room, and <br />the outside pillar of the panel (opposite the rooms), will not be pillared, as well <br />as the last rows of blocks along the northern boundary to allow for a bleeder <br />ventilation during panel mining, Partial recovery may be done for inside portions of <br />these bleeder pillars leaving sufficient support to maintain the bleeder until <br />permanent seals are completed. When an individual panel has been roomed and <br />pillared, it will be sealed before mining will begin in the next panel. Proper <br />barrier support will also be maintained. Assuming an average yearly production of <br />200,000 tons, it will take approximately 5`~ years to mine all the coal available to <br />• Blue Ribbon Coal Company, <br />Barrier zone dimensions will be 50 feet to surround the lease tract on the <br />east, west and north sides. A 20 foot minimum zone will be left between 1st and 2nd <br />North and between 2nd and 3rd North. <br />The sequence of mining will be 1st North, 2nd North, 3rd North, and <br />finally miscellaneous pillar recovery before reclaiming the property. Mining pro- <br />gresses from east to west. Within a panel, rooms will be driven only from one side. <br />In panels 1st North, 2nd North and 3rd North, those rooms shall be east. In each <br />case, the intention is that panel secondary mining will proceed from north to south. <br />The mine has encountered some difficulty in securing and stabilizing the <br />pots and slicken-sided immediate mine roof in the 1st North panel. In September 1981 <br />a teat reduction from five to three entries was initiated. The intent was to <br />evaluate a mine width less than the maximum pressure arch. As results were monitored <br />1 <br />100 (Rev. 4-I6-82) <br />