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SUBSIDENCE CONTROL PLAN <br /> The subsidence control plan which CF&I Steel Corporation plans to <br /> utilize to monitor and control the subsidence over the mine workings is <br /> three-fold. Generally , the first portion of the subsidence control plan <br /> consists of the layout of the mine in such as way that the development <br /> sections and lower recovery room and pillar sections are coincident with <br /> the reneti� able resource area. Secondly, calculations have been completed <br /> to determine the amount of subsidence in relationship to seam thickness , <br /> seam height, roof material , depth to the seam being mined, and <br /> configuration of the mine plan. The last portion of the subsidence <br /> control plan which is being utilized at the Maxwell Mine consists of <br /> monitoring a specific section to be used as a control section for <br /> relation of actual subsidence, if any, to the calculations completed <br /> during the second phase of the subsidence control plan. <br /> The mine plan which has been utilized and is shown on the Mine Plan Nap <br /> (19ap 3) , and on the Subsidence Control Plan Clap (Map 17) shows the <br /> g n ral layout of dcvel opii,-_nt and h iyher recovery areas f or the mine. <br /> Specific care has been taken to utilize a less than 50% extraction rate <br /> for areas which are overlain by renewable resources. The renewable <br /> resources in the Maxwell Mine area consist only of the alluvial valley <br /> floor at the surface adjacent to the Purgatoire River. Further <br /> discussions of the in depth research associated with the alluvial valley <br /> floor are shown in Exhibit 6, Geology and Hydrology Information. <br /> Outside of the areas which contain renewable resources , CF&I Steel <br /> Corporation plans to recover as much of the coal resource which is <br /> located in the Maxwell Mine as is possible utilizing best available <br /> mining technology. <br /> During the term of the permit application, no subsidence is expected. <br /> This is due primarily to the fact that only mine development activity is <br />