Laserfiche WebLink
to modifying the bond or the present reclamation plan, it is TCC's intent to have the foundation removed prior to <br />final grading. TR 02-40 provides the updated bond estimate for removing the piers at the prep plant facilities. This <br />• includes the prep plant, refuse bin, thickener tank and magnetite bin. This final bond estimate addresses stipulation <br />46 presented in the midterm review. <br />Fish Creek Ventilation and Dewaterine Boreholes <br />The Fish Creek ventilation borehole will require a minor amount of work in order to reclaim the site. The work <br />includes: building & duct work removal, fan removal, demolition of concrete pads, removal of concrete, sealing <br />casing, road removal, topsoil replacement, and seeding. <br />It is anticipated the ventilation shaft will have a useful life of approximately seven years, or until the first set of <br />longwall panels have been mined out. The building, duct work, and fan have been removed front the site. Until <br />final reclamation commences, the borehole will be temporarily sealed as described within the response to Rule <br />2.05.4(2)(g). At the time of final reclamation, the concrete pads will be broken up and the concrete removed from <br />the site. The material will either be hauled to the refuse site for disposal or hauled to a land fill. <br />Final reclamation of the thirty-six inch diameter casing will involve excavating down four feet from grade around <br />casing, cutting off steel casing three feet below grade, hanging steel decking from top of cut off casing (this decking <br />will be 0 feet below top of cut off casing), placement of 30 feet of concrete inside of 36 inch diameter casing, and <br />backfilling excavated area. The 30' by 3' cement plug will weigh approximately 32,000 pounds (use 150 Ibs/cf for <br />cement weight), which is adequate to provide a satisfactory seal of the shaft. The access road will be graded to <br />blend in with the surrounding topography and the culvert will be removed. The entire area will be topsoiled and <br />seeded with the appropriate seed mixture. <br />The two Fish Creek Dewatering boreholes will be sealed permanently by placement of a cement plug within each <br />. casing. The plug, for each borehole, will extend within 10 feet of the surface. The following information addresses <br />the hydrostatic conditions [hat will exist in the plugged borehole. <br />FacilityNnit Elevation <br />Boreholes 6788 <br />Portal 6800 <br />Mine roof at boreholes 5729 <br />Wadge Overburden water level 6966.9 <br />Given the above information a cement plug 1,059 feet in length and 8 inches in diameter will be placed in each of <br />the boreholes. The hydrostatic pressure at the bottom of these plugs equals the head existing between the portal <br />elevation and the mine roof elevation at the borehole plus the Wadge Overburden aquifer head. Therefore, the total <br />hydrostatic pressure at the bottom of the concrete plug equals 536 psi. Using a cement weight of 150 Ibs/cf the <br />concrete will weigh 55,449 lbs. The water force equals 26,956 lbs. Therefore, [he hydrostatic pressure is <br />approximately'/ the force of the cement plug and no problems should result from placement of the plug. <br />Southwest District Ventilation Borehole, Powerline and Access Road <br />The Southwest District Ventilation Borehole, Powerline and Access Road will require a minor amount of work in <br />order to reclaim the sites. The work includes: building & duct work removal, fan removal, demolition of concrete <br />pads, removal of concrete, sealing top of casing, powerline and pole removal, road removal, topsoil replacement, <br />and seeding. <br />It is anticipated [he ventilation shaft, and access road will have a useful life of approximately three years, or until <br />the last pane! in the S W District has been mined out. The building, duct work, fan, powerline and poles have been <br />removed from the site. The <br />TR 02-40 2.05-103 2/19/02 <br />