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surface areas disturbed. by surface operation and facilities accord to 4.09. Each plan shall describe the <br />geotechnical investi,yat.ion desi{an, construction operation maintenance and removal if ant�rooriate, of the <br />• structure and be prepared in accordance with 2.05.3(6)(b), (c) and (d) <br />RESPONSE <br />There will be no excess spoil generated from surface areas disturbed by the surface operations and facilities of the <br />Foidel Creek Mine operation. <br />Area 1 Pit Coal Waste Disposal Operations <br />Underground development waste generated from fault crossings, overcast development, and boring of ventilation <br />shafts, and material from roof falls will generally be disposed of underground in mined -out areas. 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 400,000 <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 Coal Waste Disposal Site), underground <br />development waste materials are now routed to the refuse pile for permanent placement. With construction of the <br />coal preparation plant, low quality coal stockpiled above grade adjacent to the Area 1 Pit and development waste <br />from the Area 1 Pit were removed and processed to recover saleable coal. The western portion of the Area 1 Pit has <br />been converted for interim use as a temporary water storage basin in conjunction with the mine dewatering and <br />recycle system, and has been permitted as a mine impoundment. There is some potential that all or portions of the <br />Area 1 Pit could again be utilized in the future for placement and disposal of underground development waste <br />and/or coal refuse, therefore, TCC has retained the designation of the Area 1 Pit as a coal waste disposal area. On <br />completion of operations, it is anticipated that the Area 1 Pit will be reclaimed as described under Rule 2.05.4(2)(c) <br />. by backfilling with coal waste and/or spoils, placement of a minimum of 4 feet of suitable spoil (if used for coal <br />waste only), topsoil replacement, 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 a wheel -loader, truck, or underground 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 similar to standard spoil handling <br />practices. The option also exists for coal refuse to be discharged as a slurry, on an emergency basis, to temporary <br />containment cells within the existing designated refuse disposal area. Decant from the temporary containment cells <br />would discharge to the adjacent Area 1 Pit water Storage Basin, and be handled in the same way as mine discharge <br />water. Because the Area 1 Pit is a totally incised excavation, the deposited waste materials will be confined on all <br />sides by undisturbed natural ground or backfilled mine spoils, therefore no geotechnical investigation or analyses <br />are necessary to verify operational or long-term stability for coal waste placement. Map 25, Surface Area Cross - <br />Sections, shows a typical cross-section of the disposal area (Section Y -Y), including the approximate disposal depth <br />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, and 9, Geologic Cross -Sections A -A', <br />B -B', and C -C', respectively, and as documented in Rule 2.04.6. Geochemical concentrations are largely uniform <br />in the coal, roof and floor of the underground mine. A single drillhole was chosen for coring and testing the <br />leaching potential of waste rock material, which is representative of the underground mine plan area. The location <br />of the test Drillhole 006-83-66 is shown on Map 5, Surface Geology. A lithologic log of the hole is presented in <br />Exhibit 12, Lithology Core Logs. The hole was drilled into the strata 12 feet below the Wadge Seam. Core <br />samples were collected from the roof material 5 feet above the coal seam, from the coal seam itself, and from the <br />floor material 5 feet below the coal seam. The core samples were delivered to the lab for leachate testing. In <br />addition to the core samples, aggregate samples of actual waste rock material were collected from the underground <br />mine. The aggregate samples came from roof material from roof falls, fault crossings, or overcast mining <br />operations. The aggregate samples were also delivered to the lab for leachate testing. <br />MR08-230 2.05-92 09/05/08 <br />