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Q 12i¢ht and 7 Right Crnss-Panel Rntries Grout Backfill <br />In order to mine through the 8 Right and 7 Right cross-panel entries. TCC plans to backfill with acement-flyash <br />grout. This operation will require topsoil salvage, construction of a pad for drilling and grouting operations, a <br />borehole into the 7 Right main entry, a stockpile area for flyash, and the concrete contractor's equipment. The site <br />will be used for operations associated with the backfill the 8 Right cross-panel entry, then all equipment will be <br />removed from the site for approximately one year. Equipment will be re-mobilized to the site approximately three <br />months prior to the longwall crossing of the 7 Right cross-panel entry and this entry will be backfilled. The pad <br />area will be reclaimed after the 7 Right cross-panel entry is backfiped. <br />Site preparation will require the stripping of approximately 20 inches of Clayburn loam topsoil and placing it in a <br />stockpile within the site. The footprint of the topsoil stockpile will he approxiittately 160 feet by 85 feet in a <br />crescent shape on the east side of the site. A berm wilt be placed around the stockpile and topsoil signs wilt be <br />placed on the stockpile to maintain separation from the pad area. The stockpile will be temporarily seeded with an <br />appropriate seed mixture to prevent loss of the resource. <br />The proposed pad site will cover an area of approximately 2.5 acres on the north side of Routt County Road 33 in <br />the SW 1!d of the SE 114 of S 21, T 5 N, R 86 W. The pad will be used for drilling activities and grout pumping <br />operations. Gravel wiH be placed in areas that will receive vehicular traffic in order to prevent excessive rutting of <br />the site. Approximately 820' of four strand, barbed wire fence will be constructed around the perimeter of the site. <br />Access to the site will be from either County Road 33 or the existing ranch road. Up to four temporary culverts <br />will be used at these access points to direct off-site drainage along the county road and ranch road. The culvert <br />with the largest drainage area was designed based on lire 1 year, 6 hour storm event for a minimum 6-inch <br />diameter. On-site drainage will be directed to a perimeter berm and ditch then off site through rock filters and <br />across vegetative fi]tering to Foidel Creek. <br />Mud pits will be required for the cuttings from the drilling operations and washdown of the concrete bitching plant <br />area. Three 20' s 20' ~ G deep pits are planned with a 2' high safety berm around the perimeter. Approximately <br />200 cubic yards of material from this excavation will be stockpiled immediately adjacent to the pits with the <br />remainder of excavated material being used for the construction of the safety 6enn. Up to 3S cubic yards of <br />cuttings will be placed in the mud pits. Excess capacity is provided to collect drainage from washdown, storage of <br />water, and emergency grout storage for [he concrete botching operation. The pits will remain until the site is <br />regraded for reclamation. <br />Two concrete pads are proposed to be poured at the site. A concrete pad will be 6ui1t for the mobile concrete batch <br />plant and pumping station that will be approximately 130 feet 6y i 0 feet and 6 inches thick. A concrete pad with <br />approximate dimensions of 80 feet by 40 feet by b inches thick is planned for the area where the trucks will ofy- <br />loading flyash to prevent contamination of this material with mud or gravel. <br />A borehole will be drilled into the 7 Right main entries for pwnping of the grout into the cross-panel entries. <br />Cover above the coal seam in this area is approximately 1,200 feet. The finished hole will be fully grouted to 6 '/~- <br />inch inside diameter steel pipe. Communications and the grout feed tine wilt be installed to the underground <br />workings tIIrOUgh this borehole. When the operation is complete, the hole will be plugged to the surface with <br />grout and the casing cut off a minimum of 3 feet below grade. <br />Flyash will be delivered to the site via belly-dump andlor end-dmnp trucks from either the Hayden ar Craig power <br />. plant. Up to 20,000 cubic yards of flyash will be used For each of the backfill operations. The storage pile <br />dimensions will be approximately Ia0 feet 6y 80 feet. The flyash stockpile wilt be sprayed with water to reduce <br />airborne emissions. <br />t<4R 97• i ~a 2.05-62 Revised 919197 <br />