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planned to be completed. However, CF&I Steel Corporation has completed <br /> calculations for the subsidence of the First North entries located <br /> immediately north of State Highway 12. These calculations , which are <br /> attached, indicate that no significant subsidence will occur by this <br /> mining activity. The general plan of the development entries consists <br /> of five to nine 18-foot wide entries which are driven on 90-foot <br /> centers , leaving a pillar which has an average size of approximately 72 <br /> feet to each side. Obviously, during this phase of mining , considerably <br /> less than 50% of the coal will be rcm,oved. As mining continues in this <br /> renewable resource area , a maximum of 50% of the coal will be extracted. <br /> Pillar sizes will not be less than 20 feet by 30 feet in size. <br /> Variances in pillar size will be dependent on the configuration of the <br /> development entries , rooms, and geologic factors associated with the <br /> Maxwell Seam. <br /> The monitoring program which CF&I Steel Corporation has laid out <br /> consists of nine equally-spaced, permznent monuments located on the <br /> surface and in a line perpendicular to the First North entries as shown <br /> on the Subsi�cnce Control Plan Map (Vap 17) . CF&I Steel Corporation <br /> plans to survey these monur;ents prior to mining and on a quarterly basis <br /> to determine the amount of subsidence which occurs with the mining of <br /> the First North entries. Surveying will be completed by standard <br /> transit and level survey methods common to the industry. As the <br /> monitoring program continues , the relationship of any occurring <br /> subsidence and the location of the first north mains will be reviewed to <br /> determine if it is necessary to revise the subsidence calculations which <br /> have been completed. Semi-annual reports of the subsidence monitoring <br /> program will be submitted to the Colorado Hined Land Reclamation <br /> Division. <br /> Eased on the monitoring program and its review with the subsidence <br /> calculations of this Exhibit, the extrapolated data can be used to <br /> assist CF&I Steel Corporation in planning future mining of the Maxwell <br /> Seam beneath the renewable resource lands which are present. Ongoing <br />