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surface areas disturbed by surface operations and facilities, accordin¢ to 4.09. Each plan shall describe the <br />eeotechnical investigation desitm, construction, operation. maintenance. and removal, if anorooriate, of the <br />structure and be ~renared in accordance with 2 05.3(61(61, (cl and ]dl. <br />RESPONSE <br />There will be no excess spoil generated at the surface azeas disturbed by the surface operations and <br />facilities of the Foidel Creek operation. <br />Area 1 Pit Coal Waste Disposal Operations <br />Underground development waste generated from fault crossings, overcast development, and boring of ventilation <br />sha8s, and material from roof falls will generally be disposed of underground in mined-out azeas. For a period of <br />time, any excess development waste material and/or material high in carbonaceous material was placed in the Area <br />1 Pit (a remnant surface mine pit adjacent to the Run-of-Mine Coal Stockpile), as shown on Map 24, Surface <br />Facilities. The remnant pit area has an estimated capacity for storage of waste material of approximately 40Q000 <br />cubic yards. The required fire-fighting plan for coal waste disposal operations in this area is provided in Exhibit <br />25A. <br />With construction of the Coal Refuse Pile (formerly designated as the Coa] Waste Disposal Site), underground <br />development waste materials are now routed to the refuse pile for permanent placement. With construction of the <br />coal prepazation plant, low quality coal stockpiled above grade adjacent to the Area 1 Pit and development waste <br />from the Area 2 Pit were removed and processed to recover salable coal. The Area 1 Pit has been converted for <br />interim use as a temporary water storage basin in conjunction with the mine dewatering and recycle system and has <br />been permitted as a mine impoundment. There is some potential that the Area ]Pit could again be utilized in the <br />future for placement and disposal of underground development waste and/or coal refuse, therefore, TCC has <br />retained the designation of the Area ]Pit as a coal waste disposal area. On completion of operations, it is <br />anticipated that the Area 1 Pit will be reclaimed as described under Rule 2.05.4(2)(c) by backfilling with coal waste <br />and/or spoils, placement of a min;mum of 4 feet of suitable spoil (if used for coal waste only), topsoil replacement, <br />and revegetation. <br />If utilized for placement of coal waste materials, material will be placed in the Area 1 Pit by dumping from an open <br />highwall with awheel-loader, truck, or undergound car, or will be dumped and pushed in by a tracked dozer or <br />wheel-loader. Dumped materials will be spread and compacted in a manner similaz to standard spoil handling <br />practices. Because the Area 1 Pit is a totally incised excavation, the deposited waste materials will be confined on <br />all sides by undisturbed natural ground or backfilled mine spoils, therefore no geotechnical investigation or <br />analyses aze necessary to verify operational or long-term stability for coal waste placement. Map 25, Surface Area <br />Cross-Sections, shows a typical cross-section of the disposal area (Section Y-Y), including the approximate <br />disposal depth and design postmining topography. <br />In the Area 1 Pit, the Wadge Seam was extracted by surface mining methods. The Wadge Seam and overburden <br />are part of the Williams Fork Formation of Cretaceous age. The lithology, structure and stratigraphy of the mine <br />area are fully described in Rule 2.04.6. The lithology and stratigraphy of the Wadge Seam and overburden are <br />considered to be very consistent over the mine area, as shown on Maps 7, 8, 9, Geologic Cross-Sections A-A', B-B' <br />and C-C', respectively, and as documented in Rule 2.04.6. Geochemical concentrations aze lazgely uniform in the <br />coal, roof and floor of the underground mine. A single drillhole was chosen for coring and testing the leaching <br />potential of waste rock material, which is representative of the underground mine plan area. The location of the test <br />Drillhole 006-83-66 is shown on Map 5, Surface Geology. A lithologic log of the hole is presented in Exhibit ] 2, <br />Lithology Core Logs. The hole was drilled into the strata 12 feet below the Wadge Seam. Core samples were <br />collected from the roof material 5 feet above the coal seam, from the coal seam itself, and from the floor material 5 <br />feet below the coal seam. The core samples were delivered to the lab for leachate testing. <br />TR 05-47 2.05-92 Revised -March 2005 <br />