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CY) and PPSP-1(6,000 CY). The 4,170 CY of plant growth media placed in stockpile PPSP-2 will be redistributed over the azea from which it was removed. During review of TR94-18, a concern was raised over the postmining elevation, and if the foundation would be below grade. The bond for the technical revision was established using the worst-case estimate that the foundation would have to be removed and the site then regraded. The map and certification presented in Exhibit 26B, Postmining Topography Evaluation, shows that the foundation could be at the surface upon completion of fmal grading, however given the ability to fine tune the grading plan in the field, it would be possible to keep the foundation three feet below grade. As opposed to modifying the bond or the present reclamation plan, it is TCC's intent to have the foundation removed prior to final grading. TR 02-40 provides the updated bond estimate for removing the piers at the Washplant I facilities. This includes the Washplant, Refuse Bin, Thickener, and two magnetite bins. This final bond estimate addresses Stipulation 46 presented in the Mid-Term Pemut Review. Fish Creek Ventilation and Dewaterina Boreholes The Fish Creek ventilation borehole will require a minor amount of work in order to reclaim the site. The work includes: building and duct-work removal, fan removal, demolition of concrete pads, removal of concrete, sealing the borehole casing, road removal, topsoil replacement, and seeding. It is anticipated the ventilation shaft will have a useful life of approximately seven yeazs, or until the first set of longwall panels have been mined out. The building, duct-work, and fan have been removed from the site. Until final reclamation commences, the borehole will be temporarily sealed, as described in the response to Rule 2.05.4(2)(g). At the time of final reclamation, the concrete pads will be broken-up and the concrete removed from the site. The material will either be hauled to the refuse site for disposal or to a land fill. Final reclamation of the 36-inch diameter casing will involve excavating down 4 feet below grade around the casing, cutting off the steel casing 3 feet below grade, hanging steel decking from top of the cut-off casing (this • decking will beat the top of the cut-off casing), placement of 30 feet of concrete inside the 36-inch diameter casing, and backfilling the excavated area. The 30 x 3 foot cement plug will weigh approximately 32,000 pounds (using 150 lbs/cf for cemerit weight), which is adequate to provide a satisfactory seal. The access road will be graded to blend with the surrounding terrain and the culvert will be removed. The entire area will be topsoiled and seeded with the appropriate seed mixture. The two Fish Creek Dewatering boreholes will be sealed permanently by placement of a cement plug within each casing. The plug, for each borehole, will extend within 10 feet of the surface. The following information addresses the hydrostatic conditions that will exist in the plugged boreholes: Facilitv/CTnit Elevation Boreholes 6,788 Portal 6,800 Mine roof at boreholes 5,729 Wadge Overburden water level 6,966.9 Given the above information, a cement plug 1,059 feet in length and 8 inches in diameter will be placed in each of the boreholes. The hydrostatic pressure at the bottom of these plugs equals the head existing between the portal elevation and the mine roof elevation at the borehole plus the Wadge Overburden aquifer head. Therefore, the total hydrostatic pressure at the bottom of the concrete plug equals 536 psi. Using a cement weight of 150 lbs/cf the concrete will weigh 55,449 lbs. The water force equals 26,956 lbs., therefore, the hydrostatic pressure is approximately %z the force of the cement plug and no problems should result from placement of the plug. TR07-59 2.05-103 02/27/07